Use of a mixing-coil heat exchanger combined with microwave and ultrasound technology in an olive oil extraction process Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-09-19 Alessandro Leone, Roberto Romaniello, Pablo Juliano, Antonia Tamborrino
This study addressed the possibility to improve the conditioning process of olive paste in order to make the extra-virgin olive oil (EVOO) extraction process in a continuous and rapid manner than the traditional one. An innovative heat exchanger, the mixing-coil heat exchanger (MCHE), having a mixing-coil inside was employed. Also, a continuous microwave machine (MW) and ultrasonic machine (US) prototypes were joined to it. These three prototypes were installed in a commercial olive oil extraction plant. Four conditioning processes (ML; MCHE; MCHE + ML, MCHE + MW and MCHE + US + MW) employing the prototypes were compared to the traditional one (ML) in which only one malaxer machine was employed to condition the olive paste. Olive oil extractability index (E) and olive paste rheological parameters were determined. The use of MCHE alone showed the worst results in terms of extractability (E = 74.03), having processing time of 3.84 min. Moreover, the not sufficient paste treatment didn't permit the optimal working of the three-phase decanter. Consequently, the highest solids amount in waste water was registered, compared with the other conditioning processes considered. Using the MW coupled to MCHE permitted the reduction of the conditioning time to 4.19 min instead of 40 min of ML condition, and made the process continuous, cause the employment of MW and MCHE (continuous machines) instead of ML (discontinuous machine). The E registered (85.76) resulted statistically equal to those of the traditional conditioning (E = 85.91) and MCHE − ML (E = 85.78). Conditioning time of the latter was 23.84 min. Using the three prototypes together, the investigators confirmed a process continuity and conditioning time of 5.80 min and found a value of E equal to 87.16%, not statistically different form the E value of ML conditioning process. The specific energies employed were 15.75 and 25.71 kJ kg−1 for MCHE + MW and MCHE + US + MW, respectively.Industrial relevance textThe present study addressed the use of an innovative heat exchanger, provided by an inner mixing spring, to fast condition the olive paste. It was used also in combination with an ultrasound machine and a microwave machine. The microwave machine leads to the extraction efficiency increasing and the ultrasound machine improves slightly the extraction efficiency. The results demonstrated these new technologies are able to substitute the classical malaxation operation discontinuous and time costly. Moreover, the layout of the plant resulted simplest and smallest than the traditional one.
Effect of electron beam irradiation on the functional properties and antioxidant activity of wheat germ protein hydrolysates Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-09-12 Li Wang, Ting Li, Dongling Sun, Mingquan Tang, Zheng Sun, Longfei Chen, Xiaohu Luo, Yongfu Li, Ren Wang, Yanan Li, Juan Li, Zhengxing Chen
In this paper, the effects of electron beam irradiation (EBI) on wheat germ protein hydrolysates (WGPHs) were investigated. The functional properties of WGPHs were enhanced by EBI, with the emulsifying capacity reaching its maximum value at 10 kGy. Moreover, foaming capacity reached its maximum value at 25 kGy. Additionally, EBI can enhance the antioxidant activity of WGPHs, and a dose-dependent effect was observed. Hydrolysates irradiated at 50 kGy had the greatest antioxidant activity; the DPPH and ABTS+ radical scavenging activities increased by 45.77% and 52.52%, respectively, compared to the non-irradiated sample. Additionally, surface hydrophobicity reached its minimum value at 10 kGy. After 10 kGy of irradiation, the fraction of hydrolysates with a molecular weight <1 kDa increased from 88.34% to 90.23%. Irradiation caused the surface morphology to become uneven, and it produced smaller peptides.
Effect of thermosonication and thermal treatments on phytochemical stability of barberry juice copigmented with ferulic acid and licorice extract Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-09-11 Muhammad Farhadi Chitgar, Mehran Aalami, Rassoul Kadkhodaee, Yahya Maghsoudlou, Elnaz Milani
This study was designed to compare the effect of thermosonication and thermal treatment on color and anthocyanins stability of natural and copigmented barberry juice during processing and storage. Addition of copigments significantly induced the hyperchromic effect and increased the total phenolic and antioxidant activity of barbery juice. Copigmentation especially at 1:2 M ratio, markedly enhanced the color and anthocyanin stability of barberry juice during processing. Thermal treatment negatively affected the phytochemical compounds, whereas thermosonication especially at low amplitude showed no significant changes. A similar trend in the degradation of anthocyanins and color instability of samples was observed during storage. Copigmentation, especially with licorice extract, considerably increased the half-life of anthocyanins and well preserved pelargonidin 3-glucoside and the color parameters of the juice during storage. The results indicate that licorice extract can be a good alternative to synthetic copigments and the application of thermosonication maintains the effectiveness of copigmentation reaction.Industrial relevanceBarberry (Berberis vulgaris) is one of the most important medicinal plants which is mainly cultivated in Iran. Barberry fruits are used in preparing sauces, jellies, candies, marmalades and especially juice drinks. Like other berry fruits, barberry contains high amounts of anthocyanins. Due to the highly instability of these pigments, the preservation of these nutrients during industrial processing and storage of barberry juice is very important. Intermolecular copigmentation of anthocyanins with phenolic compounds, especially with phenolic extract from various plant species, is an efficient method to stabilize these compounds. Moreover, because of the adverse effect of thermal treatment on the copigmentation reaction and the degradation of nutritive compounds of fruit juice, there is a need for non-thermal processing techniques like sonication or high pressure to preserves the nutritional and sensory properties of juices. Therefore, in this study, for the first time, the simultaneous use of thermosonication and copigmentation with ferulic acid and licorice extract on the stability of color and anthocyanins of barberry juice was evaluated. The results of our study revealed that licorice extract due to having various flavonoid compounds such as liquiritin and isoliquiritin can be a good alternative to synthetic copigments. Furthermore, the application of thermosonication in comparison with thermal treatment maintains the effectiveness of copigmentation reaction.
Effect of high pressure homogenization (HPH) on the rheological properties of taro (Colocasia esculenta (L). Schott) pulp Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-09-09 Zhen-Yu Yu, Su-Wei Jiang, Jing Cai, Xin-Min Cao, Zhi Zheng, Shao-Tong Jiang, Hua-Lin Wang, Li-Jun Pan
Our present work was undertaken to evaluate the effect of high pressure homogenization (HPH, from 0 to 60 MPa) on the steady-state shear and viscoelastic properties of taro pulp. HPH reduced taro pulp particle size, increased the dispersion of pulp particles and pulp consistency. The steady flow behavior of the native (0 MPa) and homogenized taro pulps (10–60 MPa) could be well described by the Hershel-Bulkley model. HPH increased the yield stress (σ0) and consistency index (k) of taro pulp, and decreased the flow behavior index (n). The dynamic rheological measurement showed that all the pulps (0–60 MPa) have dominant elastic properties over the viscous ones, and that the pulps could be characterized as weak gels. Moreover, HPH increased taro pulp both the storage (G′) and loss (G′′) modulus, showing that HPH improved pulp both elastic and viscous behavior. The obtained G′ and G′′ values were then modeled as a function of oscillatory frequency (ω) using the power law model. The observed increase in pulp viscoelasticity could be attributed to taro starch gelatinization and taro protein denaturation induced by HPH process, resulting in the homogenized pulps with stronger gel networks.
Thawing of frozen food products in a staggered through-field electrode radio frequency system: A case study for frozen chicken breast meat with effects on drip loss and texture Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-09-08 Tesfaye F. Bedane, Ozan Altin, Busra Erol, Francesco Marra, Ferruh Erdogdu
Radio frequency (RF) processing has been widely used for thawing – tempering purposes, and electric field distribution due to electrode design of the RF systems has significant effects on temperature increase and temperature uniformity. Therefore, the objective of this study was to investigate the electric field distribution in a staggered through-field electrode RF system and thawing temperature uniformity with changes in quality parameters during RF thawing of frozen food products. For this purpose, frozen chicken breast samples were used. Electric field distribution in the staggered through-field electrode system (10 kW – 27.12 MHz) was determined as a function of electrode gap and applied power level. Higher electric field intensity was observed at center and middle edges of the bottom electrode of the system. Hence, thawing studies were carried out placing the frozen products at the center. Upon completion of thawing, texture changes and drip losses were determined and compared with conventional thawing at 4 °C refrigeration conditions. Complete RF thawing to −0.73 ± 0.79 °C using 65 mm electrode gap took 40 min compared to 18 h of conventional thawing with significantly reduced drip losses (0.32 compared to 4.84%).
Protein enrichment of defatted soybean flour by fine milling and electrostatic separation Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-31 Qinhui Xing, Martin de Wit, Konstantina Kyriakopoulou, Remko M. Boom, Maarten A.I. Schutyser
Mechanisms of carrot texture alteration induced by pure effect of high pressure processing Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-29 Yaxin Sun, Xulei Kang, Fang Chen, Xiaojun Liao, Xiaosong Hu
The pure effect of high pressure processing (HPP) (400–1200 MPa/2 min) on carrot (Daucus carota L.) texture was investigated with minor influence of adiabatic heating. For carrot hardness and chewiness, 400 MPa result in respective loss of 71.0%, 73.8%, but no further loss was observed as pressure increased. Cohesiveness and resilience were observed to recover as pressure above 1000 MPa. Mechanisms exploration from cellular microstructure showed that carrot cells evolved from orderliness at atmospheric pressure to corrugation, elongation, collapse but partially compaction at 400, 800 and 1200 MPa, respectively, accompanied with movement of cytoplasmic content to intercellular spaces. Principal component analysis (PCA) highlighted the characteristic biochemical responses of HPP-treated carrots with pronounced ion leakage (>70%), hydrogen peroxide accumulation (>128.0%, 800–1200 MPa) and enhanced pectinmethylesterase (PME) activity (>135.2%, 400–1000 MPa). Moreover, molecular weight analysis of pectin polysaccharides showed that HPP triggered pectin depolymerisation, solubilisation of water insoluble pectin and fraction interconversion. Overall, carrot texture is interactively influenced by pressure-induced modifications on cell morphology, membrane integrity and pectin properties.Industrial relevanceApplication of HPP in industrial scale is rising. As an essential factor highly linked with freshness, texture alteration during processing is an industrial-concerned issue. This work provides information on textural alteration under a wide pressure range (400–1200 MPa). The reported pressure thresholds triggering different cellular responses of carrot tissue therefore added new theoretical basis for the industrial optimisation of high pressure conditions. The temperature control strategy used could be potentially applied in food industry with the substituted food-friendly pressure transmitting medium, as well as other areas requiring strict temperature control, for instance high pressure extraction.
Metabolic and sensory evaluation of ultrasound-assisted osmo-dehydrated kiwifruit Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-29 M. Nowacka, S. Tappi, U. Tylewicz, W. Luo, P. Rocculi, M. Wesoły, P. Ciosek-Skibińśka, M. Dalla Rosa, D. Witrowa-Rajchert
The aim of this work was to investigate the effect of ultrasound (US) pre-treatment on endogenous metabolic activity of kiwifruits slices subjected to osmotic dehydration (OD), measured by metabolic heat production in isothermal calorimeter, respiration rate, structure changes and cell viability. Moreover, the overall changes on minimally processed kiwifruit were also studied by means of electronic tongue system. Kiwifruit slices (10 mm thick) were treated with US in the bath at a frequency of 35 kHz for 10, 20 and 30 min. The OD process was conducted in a 61.5% sucrose solution at 25 °C for pre-established contact period of 0, 10, 20, 30, 60 and 120 min. The results showed that the application of US pre-treatment and OD process promoted the reduction of metabolic heat as a consequence of a partial loss of vitality. Moreover, US and US + OD treatment specifically impacted the structure and the chemical picture of kiwifruit samples.Industrial relevanceUltrasound treatment coupled with osmotic dehydration could be applied at industrial level in order to save time and energy for a further dehydration process. Moreover, fruit tissue treated with ultrasound treatment promoted structural modifications and chemical changes in the kiwifruit tissue, as resulted from the present study, which could be useful for the industries to design novel products with intermediate moisture content.
Comparison of bactericidal effects of two types of pilot-scale intense-pulsed-light devices on cassia seeds and glutinous millet Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-28 Hee-Jeong Hwang, Chan-Ick Cheigh, Myong-Soo Chung
The aim of this study was to evaluate the bactericidal effect of two types of pilot-scale intense pulsed light (IPL) devices constructed in our laboratory. Cassia seeds and glutinous millet, with initial microbial loads of 2.04 × 104 and 5.03 × 103 CFU/g, respectively, were treated by cyclone-type and belt-type IPL devices at total fluences of 3.89–54.43 J/cm2. The maximum microbial reductions of the cassia seeds and glutinous millet were 0.74, and 0.66 log/g, respectively, when using the cyclone-type IPL, and 2.63 and 0.55 log/g when using the belt-type IPL device. The geometric mean diameter of cassia seeds and glutinous millet was 0.25 and 0.13, respectively. The cassia seeds having larger particle size than glutinous millet showed a greater bactericidal effect when treated with the belt-type device. Therefore, the design of the treatment chamber can have an improved bactericidal effect on cassia seeds, demonstrating the importance of selecting a suitable IPL device according to the size of the sample to be treated.
Ultrasound as a pretreatment to reduce acrylamide formation in fried potatoes Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-24 A. Antunes-Rohling, S. Ciudad-Hidalgo, J. Mir-Bel, J. Raso, G. Cebrián, I. Álvarez
Acrylamide is a compound that is potentially carcinogenic for human. This means that levels of acrylamide in foods should be reduced to a maximum. The acrylamide molecule is present in foods subjected to processes at temperatures above 120 °C, and it is formed through the reaction that takes place between asparagine and reducing sugars in the Maillard reaction. Fried potatoes are one of the main sources of acrylamide. In order to provide healthier food, this investigation proposes to apply high intensity ultrasound (US) as a frying pretreatment in water for 30 min, in order to reduce the acrylamide content of fried potatoes. Different US treatments were studied at distinct frequencies (35 and 130 kHz), ultrasonic power densities (0, 9.5, 47.6 and 95.2 W/kg), and water temperatures (30 and 42 °C). To evaluate the effects caused by ultrasonic cavitation, the increment of weight and moisture, the decrease in reducing sugars and the electrical conductivity of water in different treatments were evaluated. After frying, colorimetric analyses (L*, a* y b*) were carried out to ascertain the indirect formation of acrylamide in potatoes. At the temperature of 42 °C, the weight gain was greater as the ultrasonic power used in both frequencies was lower. Increments in US power densities decreased the potatoes' moisture gain and increased the electrical conductivity of soaking water. A treatment of 35 kHz and 92.5 W/kg at 42 °C provided an additional extraction of 31% of the reducing sugars over that of control samples. The colorimetric parameters L * and a * decreased and increased, respectively, with the frying time for the treatment at 35 kHz/92.5 W/kg/42 °C, which are a consequence of the reduction of reducing sugars by ultrasound. Thanks to the application of this treatment, 90% acrylamide content reduction was determined compared to potatoes fried directly, and up to 50% reduction with respect to control samples only soaked in water (42 °C/30 min). This investigation has demonstrated that US pretreatments can serve as a valid strategy to reduce the acrylamide content of fried potatoes.
Effect of microencapsulated extract of pitaya (Hylocereus costaricensis) peel on color, texture and oxidative stability of refrigerated ground pork patties submitted to high pressure processing Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-20 Leda C.M. Cunha, Maria Lúcia G. Monteiro, Bruno R.C. Costa-Lima, Juliana M. Guedes-Oliveira, Victor H.M. Alves, André L. Almeida, Renata V. Tonon, Amauri Rosenthal, Carlos A. Conte-Junior
This study aimed at investigating the effect of microencapsulated microwave-assisted extracts of pitaya peel on color, texture and oxidative stability of pork patties pressurized at 500 MPa for 10 min and stored at 4 °C during 9 days. Different enhancement levels, namely 0 (NC and PNC), 100 (P1) and 1000 (P10) ppm were investigated. High pressure processing (HPP) accelerated (P ≤ 0.05) color (L* and a* values) and texture changes, as well as lipid and protein oxidation during refrigerated storage. Butyl hydroxytoluene (BHT), P1 and P10 demonstrated a protective effect (P ≤ 0.05) against the alterations promoted by HPP. Moreover, P1 and P10 demonstrated potential for inhibiting (P ≤ 0.05) protein oxidation induced by HPP and thus, minimized (P ≤ 0.05) hardness and chewiness changes in the pork matrix. Further studies should be conducted to investigate the scalability of the application at the industrial scale.
Quality changes in combined pressure-thermal treated acidified vegetables during extended ambient temperature storage Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-15 Shreya S. Kamat, Kshirod K. Dash, V.M. Balasubramaniam
A study assessed combined pressure-thermal treatment effect on quality attributes of selected acidified vegetables (banana pepper, red beets and green asparagus) over 30 days storage at 25 °C. Vegetables were acidified by suspending them in pickling liquid either through thermal blanching or 8 h storage at ambient temperature. Subsequently, samples were pressure treated in a pilot scale high pressure processor at 600 MPa, 45° or 65 °C for 5 min and stored at ambient temperature for 30 days. Quality analyses included texture, enzyme activity, color, pH and °Brix. Processed products remained stable during storage (pH < 4.0). Blanching in conjunction with combined pressure-thermal treatment (600 MPa, 45°/65 °C) inactivated the enzymes; however, it impaired texture ultimately softening the product. Results indicated that pressure treatment at 65 °C without blanching better retained quality attributes while inactivating PPO and POD (p < 0.05). Among the vegetables tested, pepper and asparagus maintained their crunchiness attribute. Industrial relevance The research documented the quality changes in selected acidified vegetable pickles subjected to various pressure-thermal treatments. By reducing thermal impact, high pressure treatment in combination with modest heat can help preserve quality attributes of acidified vegetable pickles with the extended shelf life. The knowledge from this study could help the food processors in deciding relevance of high pressure processing for industrial manufacturing of acidified low-acid shelf-stable vegetable matrices.
Atmospheric-pressure plasma treated water for seed germination and seedling growth of mung bean and its sterilization effect on mung bean sprouts Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-08 Jiangwei Li, Renwu Zhou, Rusen Zhou, Xianhui Zhang, Size Yang
Quantitative microbial assessment for Escherichia coli after treatment by high voltage gas phase plasma Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-07 Višnja Stulić, Tomislava Vukušić, Anet Režek Jambrak, Višnja Bačun-Družina, Dean Popović, Jasna Mrvčić, Zoran Herceg
High voltage electrical discharge (gas and liquid) plasmas are new developing techniques used for food and water decontamination. This study investigates the influence of high voltage gas phase plasma treatment on several parameters: inactivation of Escherichia coli K12, recovery, proteomic analyses, cellular leakage and influence of pH and generated H2O2 species on inactivation of the E. coli cells. Samples were treated in a glass reactor with a point-to-plate electrode configuration. Electrical conductivity (100 and 800 μS/cm), polarity (+/−), time (5 and 10 min) and frequency (60, 90 and 120 Hz) were chosen in order to determine their influence on listed parameters. Statistical analyses were obtained to optimize conducted treatments. Treatment regime of 90 Hz, positive polarity, 100 μS/cm and 10 min resulted in the highest reduction (7.8 log10 CFU/mL) of E. coli. Recovery of cells after the treatment suggested oxidative stress overcome. Industrial relevance Plasma processing is an energy effective process, comparing to traditional thermal processes like pasteurization and sterilization. Plasma treated liquid remains at low temperature, which lowers electrical energy consumption during industrial processes. The proposed study investigates the possible application of high voltage gas phase electrical discharge plasmas for inactivation of Escherichia coli K12 MG1655 in water. The main aim was to confirm effectiveness of plasma treatment conducted in argon (which is uninfected by plasma and can be recycled) on inactivation and cell recovery of E. coli K12. This research is a first step towards the development of the gas phase plasma technology for disinfection of liquids. However, future development, optimization and application of this technology for food sterilization will lead to acceptable ecological regulations like lowering greenhouse gas emissions.
Influence of compositional characteristics and high pressure processing on the volatile fraction of Iberian dry-cured ham after prolonged refrigerated storage Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-05 Nerea Martínez-Onandi, Ana Rivas-Cañedo, Antonia Picon, Manuel Nuñez
The effect of high pressure processing (HPP) at 600 MPa and refrigerated storage for 5 months on the volatile fraction of 30 Iberian dry-cured hams of different compositional characteristics was investigated. Compositional characteristics significantly influenced 11 compounds (3 alcohols, 3 carboxylic acids, 2 alkanes, 2 benzene compounds and 1 aldehyde) out of the 116 compounds identified in the volatile fraction of Iberian ham. HPP treatment had a significant effect on 34 volatile compounds, with higher levels of 11 compounds and lower levels of 23 compounds in HPP-treated samples than in control samples. Refrigerated storage for 5 months significantly influenced the levels of 75 compounds, 25 of which appeared or increased while 50 disappeared or decreased. During that period, the total abundance of volatile compounds decreased by 5.1% in control ham and 1.3% in HPP-treated ham. Iberian ham commercial shelf life should be limited to maintain its sensory characteristics. Industrial relevance HPP treatment and refrigerated storage of dry-cured ham are advantageous industrial and commercial procedures. In the particular case of Iberian ham, both HPP and refrigerated storage brought about a decrease in the total levels of volatile compounds. Therefore, adequate HPP treatment conditions and commercial shelf life should be cautiously set in order to safeguard the unique odor and aroma characteristics of Iberian ham.
Combined effect of pulsed electric field and osmotic dehydration pre-treatments on mass transfer and quality of air dried goji berry Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-05 E. Dermesonlouoglou, A. Chalkia, G. Dimopoulos, P. Taoukis
Pulsed electric field (PEF) and osmotic dehydration (OD) pre-treatments can improve the slow and energy intensive process of goji berry drying. The effect of PEF and OD processing conditions on mass transfer, color, antioxidant capacity and total phenolic content was studied. Application of PEF (0.9–2.8 kV/cm, up to 7500 pulses) caused tissue permeabilization (electrical conductivity disintegration index, Zp, value up to 0.38, due to the structure of goji berry waxy peel) and significantly enhanced mass transfer during subsequent OD and air drying (increased effective diffusivity coefficients Dew and Des and drying rate kdrying respectively). Combining OD (55 °C, 60 min), PEF (2.8 kV/cm, 750 p) and air drying (60 °C) compared to conventional air drying led to total processing time decrease (by 180 min or 33%), better color retention, higher antioxidant capacity and total phenolic content.
Experimental and theoretical analysis of drying grapes under an indirect solar dryer and in open sun Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-04 Hajar Essalhi, Mohamed Benchrifa, Rachid Tadili, Mohammed Najib Bargach
In the present work, the drying behavior of grapes under open sun and into indirect solar dryer was studied. The indirect solar dryer was designed in the Solar Energy and Environment Laboratory of Mohammed V University, Rabat, Morocco. It consists of a solar collector, a heat exchanger, a water storage tank and a drying chamber. Results show that during off sunshine hours, the heat transfer from the water storage tank kept the grapes temperature higher than ambient temperature. Drying results indicated that the times required for drying grapes starting at the initial moisture contents of 79.8% (w.b.) till final moisture contents of 20.2% (w.b.) were 120 h and 201 h in indirect solar and open sun drying, respectively. The drying data were fitted to 10 thin-layer drying models to describe and compare the drying characteristics of the grapes. Comparisons were based on the coefficient of correlation (R), root mean square error (RMSE) and reduced chi-square (χ2). Midilli et al. model is found to best depict grapes drying behavior in both indirect solar and open sun drying. The evaluated values of the effective moisture diffusivity of grapes sun drying and grapes indirect solar drying when applying the Fick's diffusion model were 2.34 × 10−11 and 4.08 × 10−11 m2/s, respectively.
Ethanol and ultrasound pre-treatments to improve infrared drying of potato slices Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-04 Meliza Lindsay Rojas, Pedro E.D. Augusto
Ethanol and ultrasound (US) were applied as pre-treatments to improve the infrared (IR) drying of potato slices. Pre-treatments included Control samples (Without any pre-treatment), samples immersed in ethanol (Ethanol treated) and treated with US using ethanol (Ethanol + US) and water medium (Water + US). Effects on microstructure, drying, rehydration, and viscoelasticity were studied. Microstructure analyses suggested that ethanol affected the potato cell wall. The Water + US pre-treatment impacted the starch granules dispersion inside cells. However, higher modifications were observed when Ethanol + US was applied. Compared to the Control, all pre-treatments decreased the drying time, while Ethanol + US provided the highest reduction. In contrast, a slight decrease in rehydration properties was observed. The dried and rehydrated samples presented similar viscoelasticity among them but differed significantly with the in-natura (fresh potato) samples. Possible mechanisms were discussed. The results open new perspectives about an innovative method to improve drying.
Synergistic effect of 3,4-dihydroxyphenylglycol with hydroxytyrosol and α-tocopherol on the Rancimat oxidative stability of vegetable oils Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-04 Antonio Lama-Muñoz, Fátima Rubio-Senent, Alejandra Bermúdez-Oria, África Fernández-Prior, Juan Fernández-Bolaños, Guillermo Rodríguez-Gutiérrez
The current work evaluated the ability of pure 3,4-dihydroxyphenylglycol (DHPG) and hydroxytyrosol (HT) in combination with a commercial phenolic extract from Olea europaea rich in HT to prevent the oxidation of edible vegetable oils. The commercial phenolic extract was highly soluble in all matrices and significantly improved the oxidation stability and delayed the onset of rancidity of oils compared to a control (with no antioxidant). The combinations of DHPG with other natural antioxidants, such as HT and α-tocopherol, showed that it can be a useful supplement to increase the shelf life of sunflower oil. Synergism was observed when DHPG and HT were added in combination. The synergistic effect was directly related to the concentration ratio between both antioxidants. The mixtures containing DHPG/α-tocopherol and DHPG/HT/α-tocopherol also showed effectiveness in delaying oxidation.
3D printed milk protein food simulant: Improving the printing performance of milk protein concentration by incorporating whey protein isolate Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-02 Yaowei Liu, Dasong Liu, Guanmian Wei, Ying Ma, Bhesh Bhandari, Peng Zhou
This paper aimed to establish a milk protein based 3D printing food simulant and investigated the effect of whey protein isolate (WPI) concentration on the printing performance of milk protein concentrate (MPC). WPI and MPC powders at different ratios were prepared in paste (35 wt%, total dry matter content). The rheological properties and water distribution of protein matrix prepared with different MPC/WPI ratios were characterized with a rheometer and low field nuclear magnetic resonance (LF-NMR), respectively. Moreover, the variations in the microstructure of printed objects were observed with a scanning electron microscope (SEM). The printed objects showed different appearance and physical properties; the printing fidelity was also evaluated by measuring the geometric accuracy of printed objects. The rheological and texture data showed that the presence of WPI could reduce the apparent viscosity and soften the MPC paste, benefiting the printing process. The results showed that the milk powder paste mixture prepared with MPC/WPI at a ratio of 5/2 was the most desirable material for extrusion-based 3D printing, which could be successfully printed and matched the designed 3D model best.Industrial relevance3D printing in food sector has been an attractive and emerging technology owing to its potential advantages, such as customized food designs, personalized and digitalized nutrition, simplifying supply chain and so on. This paper established a high protein food simulant for 3D printing, optimized its printing performance with whey protein isolate, and studied the physicochemical property of prepared protein pastes. The overall results indicated that milk protein powders could be the promising materials for the application in food 3D printing. In flowing studies or practical production, the glycerol could be replaced by ingredients such as syrup, honey etc. This study may give more insights into 3D printing applied in food sector and facilitate the further developments of 3D food printing.
Microwave-assisted pasteurization of beverages (tamarind and green) and their quality during refrigerated storage Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-01 Arnold David González-Monroy, Gabriela Rodríguez-Hernández, César Ozuna, María Elena Sosa-Morales
Microwave-assisted treatments for the pasteurization of a tamarind and green (formulated with pineapple, nopal, guava, and lemon juice) beverages were studied. The beverages were treated with microwaves (490 W, 2450 MHz) in batches of 480 mL until reach the target temperature for the inactivation of the enzyme pectinmethylesterase (90 °C, with holding time of 12 s). Thermal images were taken after the treatments to guarantee the heating uniformity. Bottles were closed, cooled and stored in refrigeration for 21 days. The heating time was 255 s and 280 s for the green and tamarind beverages, respectively. Enzymatic activity was reduced 100% and microbiological accounts were depressed after MW-pasteurization. There were no significant changes in pH, titratable acidity and total soluble solids in tamarind beverage in comparison with untreated samples (p > 0.05). However, MW-pasteurization affected sensory attributes and color in the green beverage (p < 0.05). Industrial relevance Microwaves (MW) are an alternative among the emerging technologies for preservation of diverse fluid foods, with advantages such as, high efficiency, sustainability and reduction of time and costs. This study found viable MW-pasteurization to preserve the sensory, physicochemical and microbiological properties of the tamarind beverage even for 21 days under refrigeration. Despite a safe and stable product may be obtained, the color and sensory attributes should be improved for green beverage. The proposed batch microwave-assisted pasteurization is a short treatment, which can be applied in small facilities or rural zones, with potential to be scaled up it to an industrial level.
Comparison of enzymatic and precipitation treatments for gluten-free craft beers production Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-08-01 Mauro Fanari, Mauro Forteschi, Manuela Sanna, Manuel Zinellu, Maria Cristina Porcu, Luca Pretti
Celiac disease and non-celiac gluten sensitivity are both related to gluten consumption. In sensitive subjects, gluten triggers an immune-mediated enteropathy for which no therapy is yet available. Beer must be avoided by gluten sensitive subjects, since it is generally made from gluten containing grains such as barley and wheat. In this study we compared two different deglutinization treatments on an American India Pale Ale, brewed on a craft beer pilot plant: an enzymatic process based on Aspergillus niger prolyl endopeptidase and a precipitation process by silica gel. The gluten amount in all stages of brewing, and the effects of treatments on standard quality attributes, chemical composition and sensory profile were evaluated. Both treatments were able to reduce gluten level below 20 ppm, showing a different behavior. Only slight differences were observed in the chemico-physical characteristics of treated and untreated beers, whereas sensory analysis did not highlight any change. Industrial relevance Considering the massive increase of microbreweries and the grown of gluten-free products market, two different deglutinization treatment were compared in pilot plant production of craft beer. Results show how it is possible to produce a gluten-free beer from traditional ingredients. The slight differences observed between treatments had no impact on the sensory profile, allowing to brew high quality gluten-free beers.
Changes in soybean trypsin inhibitor by varying pressure and temperature of processing: A molecular modeling study Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-07-30 Sai Kranthi Vanga, Ashutosh Singh, Vijaya Raghavan
In recent years, molecular dynamic (MD) simulations have been used to understand the effects of various processing methods on the structural properties and stability of proteins. In this study, the conformational changes in soybean trypsin inhibitor molecule were evaluated with the use of high temperature and pressure. The MD simulations have been performed at various temperatures (300 K, 345 K and 373 K) and pressure (1 bar, 3 kbar, 6 kbar) combinations. The results showed that the soybean trypsin inhibitor (STI) molecule is relatively stable at high temperatures, primarily due to the presence of disulphide bonds. However, at higher pressures, significant compaction was observed. Root mean square deviations, Radius of gyration and volume of the STI molecule were evaluated. Furthermore, Ramachandran plots were used to evaluate the stability of the various simulated molecules. It was found that the compaction resulted in high steric interferences among the core residues.
Inactivation of peroxidase and polyphenoloxidase in coconut water using pressure-assisted thermal processing Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-07-25 Angelica M. Chourio, Fabiola Salais-Fierro, Zahid Mehmood, Sergio I. Martinez-Monteagudo, Marleny D.A. Saldaña
The effect of pressure assisted thermal processing (PATP) was evaluated on the inactivation kinetics of polyphenol oxidase (PPO) and peroxidase (POD) and selected quality attributes of coconut water. Coconut water from green young coconuts was treated at 200, 400 and 600 MPa, 40–90 °C, and 60–1800 s of holding time. The activities of PPO and POD were determined using spectrophotometric methods. No enzymatic activity was detected for both enzymes within 300 s at 90 °C/400–600 MPa. The combination of 400 MPa/90 °C/300 s yielded POD and PPO inactivation, and could be used in the industrial development of PATP treated-coconut water. The POD showed to be more pressure-temperature resistant than the PPO in coconut water. The pressure-temperature inactivation kinetics of PPO and POD in coconut water were well described by the Weibull model. The activation energy for the inactivation of POD and PPO were 107–192 and 41–191 kJ mol−1, respectively, while the activation volume varied from −13.2 to 10.2 and −37 to 9.2 cm3 mol−1, respectively. Total phenolic content extractability significantly increased after PATP treatments at all conditions evaluated compared to the control. Low ∆E values of PATP treated coconut water were obtained, indicating imperceptible change of color. Industrial relevance Pressure Assisted Thermal Processing (PATP) is an emerging technology that requires further research. The results of this study highlighted for the first time the potential of PATP on polyphenoloxidase and peroxidase inactivation of coconut water, maintaining color characteristics of coconut water. The pink color after PATP treatment was not observed. In addition, the use of kinetic models helped to determine the optimal conditions for enzyme inactivation. The outcomes of this study can be used for further industrial development of PATP treated-coconut water.
Modeling of permeate flux decline and permeation of sucrose during microfiltration of sugarcane juice using a hollow-fiber membrane module Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-07-25 Chirasmita Panigrahi, Sankha Karmakar, Mrinmoy Mondal, Hari Niwas Mishra, Sirshendu De
Microfiltration (MF) of centrifuged sugarcane juice was used as a pre-clarification step prior to further clarification. MF was performed with the objectives of achieving maximum flux, minimum retention of sucrose and maximum rejection of total solids as well as maximum removal of microorganisms from the permeate keeping the nutritional and physico-chemical profile intact. In this regard, experiments were done using a polyacrylonitrile-based MF membrane of filtration area 0.027 m2 and pore size of 0.1 μm. A detailed investigation of the effects of different operating conditions, namely transmembrane pressure TMP (35, 69, 104 and 138 kPa) and cross flow velocity CFV (0.123, 0.246 and 0.369 m/s) on membrane productivity and juice quality was undertaken. The steady-state permeate flux ranged from 5.41 to 6.23 l/m2∙h for the domain of the operating conditions studied herein. Profiles of permeate flux and sucrose concentration in permeate were modeled using a gel layer controlling model under the framework of boundary layer analysis. The optimized operating conditions were found to be TMP of 104 kPa and CFV at 0.369 m/s, yielding a flux of 6.04 l/m2∙h and having sucrose and polyphenols concentration of 104.8 g/l and 9.38 mg GAE/100 ml, respectively. Total solids (26%) and turbidity (98%) were removed to a great extent during MF along with remarkable improvement of clarity (3 times). Microbiological evaluation confirmed that, MF successfully reduced the total viable plate count by 5 log CFU/mL scale and yeast and mold count by 4 log CFU/mL scale.
Plasma activated water and airborne ultrasound treatments for enhanced germination and growth of soybean Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-07-24 Chiara Lo Porto, Dana Ziuzina, Agata Los, Daniela Boehm, Fabio Palumbo, Pietro Favia, Brijesh Tiwari, Paula Bourke, Patrick J. Cullen
The effect of two novel technologies, also in combination, on germination and growth of soybeans has been investigated. On one side, ultrasound treatment of the seeds increased water uptake without altering the morphology and the wettability of the seed coat, but also induced slight chemical modifications of the outer part of the seed. Plasma-activated water (PAW), obtained from treating water with non-thermal atmospheric-pressure plasma in air, increased the rate of germination and subsequent plant growth. Different combinations of these two technologies were tested in order to study their interaction and to identify an optimum treatment process. Industrial relevance A great urgency in crop management is to enhance sustainability. The aim is to achieve a cheap and eco-friendly production process reducing the wide current use of energy, irrigation water, chemicals and pesticides. Soybeans is a legume whose worldwide production is increasing in the last years therefore a higher efficiency and sustainability in its cultivation is obviously very appealing. Cold plasma and Ultrasound technologies are well-known in the industrial scenario and their applications in crop production are recently drawing attention; the potential of combining these two powerful techniques is clearly very promising.
Olive oil nutritional labeling by using Vis/NIR spectroscopy and compositional statistical methods Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-05-22 José A. Cayuela-Sánchez, Javier Palarea-Albaladejo
Food nutritional labeling is compulsory in the European Union since 13 December 2016. The olive oil fatty acid composition shows high variation depending mainly on the variety. Thus, olive oil nutritional labeling is problematic for the industry. Besides, the analysis of all batches of olive oil using the official methods is expensive. Therefore, the olive oil industry is seriously concerned about solutions for nutritional labeling. In this study, a new rapid technique to measure the nutrients for the olive oil nutritional labeling, is assessed. A novel partial least squares (PLS) calibration model using log-ratio coordinates has been formulated and successfully tested for predicting the percentages of monounsaturated, saturated, and polyunsaturated fatty acids based on visible and near infrared spectroscopy. The model provided accuracy suitable for labeling, under the rules in force in the European Union. The error was generally much lower than the tolerance. Industrial relevance The approach here proposed can be a suitable solution for olive oil nutritional labeling, which is a current challenge for the olive oil industry.
Pulsed Electric Field treatment after malolactic fermentation of Tempranillo Rioja wines: Influence on microbial, physicochemical and sensorial quality Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-05-22 Lucía González-Arenzana, Javier Portu, Noelia López, Pilar Santamaría, Ana Rosa Gutiérrez, Rosa López, Isabel López-Alfaro
During wine stabilization, control of the microbial population is required in order to ensure a quality wine. Pulsed Electric Field (PEF) was applied to commercial wines in a continuous flow to reduce the amount of SO2 added after the end of malolactic fermentation to manage microbial populations. Samples of wine from three commercial wineries of the Rioja Qualified Designation of Origin were treated with 30 mg/L SO2, with 15 mg/L SO2 and PEF, and only with PEF. The inactivation of the microbiota with the PEF treatment was greater than the inactivation achieved with SO2 four days after treatment. Six months later, the lactic acid bacteria population was still viable in some of the wines. Regarding the physicochemical characterization of the wines, the PEF treatment was positive for quality because the wines had greater color intensity and lower volatile acidity. Moreover, organoleptic analysis indicated different scoring depending mainly on the characteristics of the original wine. Despite these positive results, further studies are advisable to optimize the control of lactic acid bacteria. Industrial relevance The application of PEF during wine stabilization after MLF can be a viable alternative for the oenological industry to reduce the SO2 dosage used in winemaking.
Olive mill wastewater as a potential source of antibacterial and anti-inflammatory compounds against the food-borne pathogen Campylobacter Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-05-19 Jose Manuel Silvan, Manuel Alejandro Pinto-Bustillos, Pablo Vásquez-Ponce, Marin Prodanov, Adolfo J. Martinez-Rodriguez
Phenolics and secoiridoids from crude olive mill wastewater (OMW) were purified using a preparative hybrid separation process: pressure-driven cross-flow membrane micro-(MF) and ultrafiltration (UF) and solid phase extraction (SPE). Five fractions with different contents of these compounds were obtained and their antibacterial activity against several strains of Campylobacter was evaluated. The results showed that the fraction with the highest content of phenolic and secoiridoid compounds had a relevant antibacterial activity against all tested strains with a strain-dependent character. Pre-treatment of LPS-stimulated cells with this fraction decreased the production of nitric oxide (NO), showing its potential as anti-inflammatory agent. Finally, the effect of the same fraction on the viability of human intestinal epithelial cell lines was evaluated. In conclusion, OMW could be useful as a potential source of bioactive compounds against Campylobacter, increasing the valorisation of olive oil by-products.
Thermally-treated strawberry extrudate: A rich source of antioxidant phenols and sugars Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-05-19 Guillermo Rodríguez-Gutiérrez, Juan Cubero Cardoso, Fátima Rubio-Senent, Antonio Serrano, Rafael Borja, Juan Fernández-Bolaños, Fernando G. Fermoso
Strawberries have antioxidant, cardiovascular, and antiproliferative properties. The agroindustrial production of strawberry concentrate generates a food waste after extrudation that is usually landfilled. This strawberry extrudate is a rich source of valuable bioactive compounds such as phenols and sugars. In the present study, industrial thermal treatments currently in use for the valorization of other agricultural wastes were determined to be suitable for the treatment of strawberry extrudate. Thermal treatment conditions in the range of 90 °C to 200 °C were studied. Thermal treatment at 150 °C for 60 min without acid addition was the most efficient process based on the solubilization of sugars and phenols as well as the antioxidant capacity of the liquid phase produced. Instead of sending this residual fraction to landfill, such treatment would permit the use of strawberry extrudate as a source for the recovery of valuable bioactive compounds.
Combined effect of cold atmospheric plasma, intrinsic and extrinsic factors on the microbial behavior in/on (food) model systems during storage Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-05-19 C. Smet, M. Baka, L. Steen, I. Fraeye, J.L. Walsh, V.P. Valdramidis, J.F. Van Impe
Microbial decontamination by means of cold atmospheric plasma (CAP) offers great potential for treatment of heat-sensitive food products, extending their storage life. CAP is created by applying a high voltage to a gas stream, resulting in microbial inactivation according to different mechanisms. This paper thoroughly assesses the influence of CAP on the storage life of food model systems inoculated with Salmonella Typhimurium. (Food) model systems, with varying intrinsic factors (pH, salt concentration, and food (micro)structure), are treated for 5 min using a dielectric barrier discharge reactor generating a helium‑oxygen plasma. Following treatment, the impact of extrinsic factors is evaluated by storage at 8 °C or 20 °C. During storage, cell densities are determined. Data are fitted with predictive (growth or inactivation) models. As additional experiments indicate that the CAP treatment itself has a limited or even negligible effect on the properties of the model system (pH, aw, (micro)structure), the microbial behavior of CAP treated samples during storage can be attributed to the treatment. CAP treatment can result in microbial reductions up to 2.7 log10 and prolongs storage, however its rate of success is dependent on both extrinsic and intrinsic factors. An important factor is the storage temperature, as recovery of CAP treated cells proves more difficult when stored at 8 °C. At 20 °C, cell growth is merely slowed down. Additionally, at pH 5.5, 6% (w/v) NaCl, osmotic stress is induced on the microorganisms, which results in low cell recovery or further inactivation. The influence of the food (model) structure on the storage behavior is insignificant. Industrial relevance Although being a very promising technology, most studies regarding the use of cold atmospheric plasma (CAP) for food decontamination focus on the inactivation of a target microorganism, in relation to a specific food product. Fundamental knowledge on this non-thermal technology, including its impact on the storage life, is lacking. This study investigates the effect of CAP on the microbial behavior during storage. By performing tests on model systems, for a variation of intrinsic and extrinsic factors, this work renders information on the suitability of this novel technology regarding treatment of a broad spectrum of food products. Moreover, this study demonstrates the limited impact of CAP on the food (model) properties, enhancing the suitability of the technology to be implemented in the food industry.
By-products of the rice processing obtained by controlled debranning as substrates for the production of probiotic bacteria Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-05-12 Premsuda Saman, Pablo Fuciños, José A. Vázquez, Severino S. Pandiella
Cereal debranning is a milling process in which bran layers are sequentially removed by controlled abrasion. Six rice fractions were produced with increasing debranning degrees: A (0–2.3% w/w), B (2.3–3.8% w/w), C (3.8–5% w/w), D (5–6.3% w/w), E (6.3–7.3% w/w) and F (7.3–100% w/w). Fermentation media were prepared from all fractions, and evaluated for supporting the growth of two probiotic strains, Lactobacillus plantarum NCIMB 8826 and Lactobacillus reuteri NCIMB 8821. Biomass, substrate consumption, and lactic acid production were accurately modelled using an unstructured mathematical model. A 3.7% (w/w) debranning degree resulted optimal in stimulating the growth of the selected probiotic strains. Results obtained suggest that this fraction might be suitable for producing potential synbiotic formulations. Industrial relevance There are many health benefits associated with the consumption of synbiotic foods, combining probiotic bacteria and prebiotic compounds. The development of rice-based synbiotic products might be an approach, offering a healthy alternative for individuals with, for instance, lactose intolerance.
Hyperbaric cold storage: Pressure as an effective tool for extending the shelf-life of refrigerated mackerel (Scomber scombrus, L.) Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-05-07 L. Otero, M. Pérez-Mateos, F. Holgado, G. Márquez-Ruiz, M.E. López-Caballero
The efficacy of hyperbaric cold storage for preserving lean fish has been recently demonstrated but, to the best of our knowledge, no data exist for fatty fish. To evaluate the effect of hyperbaric cold storage on the shelf-life and quality of fatty fish, we stored Atlantic mackerel fillets at 5 °C, both at atmospheric pressure and at 50 MPa. After 12 days of hyperbaric storage, no microbial growth was observed. Thus, most counts were similar or slightly lower than those of control samples at day 0, while H2S-producing organisms and sulphite-reducing bacteria reduced under the detection limits. Moreover, no significant lipid degradation was observed. By contrast, increased microbial counts and significant lipid hydrolysis were detected in the samples stored at atmospheric pressure. Moreover, even though the protein profile was significantly altered during hyperbaric storage, most fish-quality indicators (pH, TVB-N, drip loss, water-holding capacity, and firmness after cooking) were better preserved in the mackerel samples stored at 50 MPa. These results clearly prove that hyperbaric cold storage was more efficient than conventional refrigeration for the preservation of Atlantic mackerel fillets. Industrial relevance Long-term preservation of fatty fish is a challenge for the seafood industry mainly due to lipid degradation that can rapidly reduce fish quality. If effective against lipid degradation, hyperbaric cold storage could be an interesting technology to preserve fish and fish products. The increased cost resulting from hyperbaric storage should be overcome by an extended shelf-life of a high-quality product.
Microbial and chemical characterization of commercial washing lines of fresh produce highlights the need for process water control Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-05-05 Francisco López-Gálvez, Juan A. Tudela, Ana Allende, Maria I. Gil
Process wash water and washed products from three different fresh produce processing lines were characterized at commercial scale. Different physicochemical and microbiological characteristics of wash water were measured. Great variability between processing lines on the physicochemical quality of process wash water was observed, caused in part by the type of produce washed. The relationship between lower aerobic mesophilic bacteria and higher free chlorine (FC) concentrations in wash water was detected (Pearson's correlation coefficient (PCC) = −0.53). Independently of the FC concentration, most of the water samples (>80%) showed presence of cultivable (limit of detection 1 CFU/100 mL), probably caused by the uncontrolled pH conditions. Higher values of FC and oxidation-reduction potential (ORP) in wash water were related to lower microbial load in washed produce (PCC = −0.82, and − 0.79, respectively). Higher concentration of chlorine was linked to a higher presence of disinfection by-products (DBPs) in the wash water, and washing in chlorinated water led to a significant increase in the concentration of DBPs in produce. However, the accumulation of trihalomethanes (THMs) in process wash water was not correlated with higher concentrations of these DBPs in produce. Industrial relevance The washing step of fresh produce processing lines is a critical process. The dose of disinfectants needs to be adequately optimized to avoid microbial contamination without generating the accumulation of disinfection by-products (DBPs). In this study, critical parameters that influence the efficacy of water disinfection and the occurrence of DBPs in fresh produce processing lines were identified under commercial conditions. The results evidenced that monitoring and control of pH play a critical role by maximizing the concentration of the most active form of chlorine in the water. The parameter UV254 measured on-line in the washing tank, can be suggested as a suitable indicator of the presence of organic matter in fresh produce wash water.
Some new findings on the potential use of biocompatible silver nanoparticles in winemaking Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-04-26 Irene Gil-Sánchez, Miguel Monge, Beatriz Miralles, Gloria Armentia, Carolina Cueva, Julian Crespo, Jose M. López de Luzuriaga, M. Elena Olmos, Begoña Bartolomé, Dolores González de Llano, MaVictoria Moreno-Arribas
There is currently an increasing commercial demand for silver nanoparticles (Ag NPs) due to their wide applicability in various markets. Because of their powerful antimicrobial properties, these nanoparticles are frequently used for food-associated consumer products. In this paper, the effect of two Ag NPs coated with biocompatible materials – PEG-Ag NPs 20 (polyethylene glycol) and GSH-Ag NPs (reduced glutathione) – to control microbial growth in wines was assessed. Both Ag NPs were subjected to an in vitro three-step digestion, and changes in their morphology and an assessment of their cytotoxicity against Caco-2 cells were determined. Both Ag NPs were effective against the different microbial population present in tested wines. Regarding their in vitro digestion, the size and shape of the nanoparticles were almost unaltered in the case of GSH-Ag NPs, while in PEG-Ag NPs 20 some particle agglomeration was observed. Overall, these results suggest that Ag NPs may reach the intestine in a nano-scaled form. Finally, Caco-2 cell experiments seemed to exclude toxicity of Ag NPs at the intestinal epithelium. Industrial relevance Traditionally, sulphur dioxide (SO2) has been used by oenologists to control the microbial population in wine. As a result of increasing evidence of possible health risks associated with this additive in wine, there has been growing interest in finding new alternatives to replace it. Silver nanoparticles display a broad spectrum of antimicrobial activity, so they could constitute a very promising approach to reducing SO2 in winemaking.
Iron bioavailability from food fortification to precision nutrition. A review Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-04-23 Ruth Blanco-Rojo, M. Pilar Vaquero
Iron deficiency anaemia is a Worldwide Public Health problem and the fortification of food with iron is the most cost-effective prevention strategy. The correct combination of iron form and food vehicle is crucial, as well as the dietary context of consumption. Combinations of iron with an enhancer of its bioavailability and avoidance of interaction with iron inhibitors are recommended. New iron fortificants, innovative complexes, coatings and nanoparticulates, and biofortification are the main research lines. Ultimately, human assays are necessary before industrial production. In this regard, precision nutrition helps to identify the vulnerable groups that, according to genotype, dietary habits, physical activity and, most recently, metagenomic profile, may benefit from a specific iron-fortified food. This review addresses the modifiers of iron bioavailability and the main aspects to take into account in the development of iron-fortified food to prevent iron deficiency. Industrial relevance • The potential target population that would benefit from iron-fortified foods is that at risk of iron deficiency. However, there are also segments of population at risk of iron overload. • Iron fortification involves complex technological issues, but the economic impact is very high. • Research on “omics” sciences delivers scientific results applicable to the design and production of iron-fortified food.
Antimicrobial and antioxidant effects of combined high pressure processing and sage in beef burgers during prolonged chilled storage Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-04-17 L. Mizi, S. Cofrades, R. Bou, T. Pintado, M.E. López-Caballero, F. Zaidi, F. Jiménez-Colmenero
The combined effect of sage (0.3 and 0.6%) and high pressure processing (HPP) [300 MPa (10 min, 9.9 °C) and 600 MPa (10 min, 10.2 °C)] on the antimicrobial and antioxidant characteristics of beef burgers during prolonged chilled storage (60 days) was analysed. Sage powder showed antioxidant and antimicrobial activities, but the addition of sage powder to burgers had no apparent effect on antimicrobial activity; however, antioxidant activity was detected as measured by TBARS, hexanal and photochemiluminescence (PCL). In general, lipid oxidation increased in all samples during storage. HPP at 600 MPa had no effect on lipid oxidation but caused mesophilic and psychrotrophic counts to remain close to the detection limit for at least 6 days. Significant correlations were found between lipid oxidation measured by TBARS and PCL and between TBARS with hexanal over the storage period. Sage had no detrimental effects on sensory attributes of burgers. Industrial relevance Sage is an aromatic plant with excellent antimicrobial and antioxidant properties. High pressure processing (HPP) is an efficient non-thermal preservation technology. As far as the authors are aware, very few studies have holistically addressed the question of stability (microbial spoilage and oxidation of lipids) of traditionally-prepared burgers as affected by HPP and addition of a natural plant. This paper examines the possible application of both treatments so as to obtain beef burgers with suitable oxidative and microbiological stability over prolonged chilled storage without this affecting sensory attributes.
Electrospraying assisted by pressurized gas as an innovative high-throughput process for the microencapsulation and stabilization of docosahexaenoic acid-enriched fish oil in zein prolamine Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-04-09 M.A. Busolo, S. Torres-Giner, C. Prieto, J.M. Lagaron
Zein, a prolamine obtained from maize, was employed to encapsulate a fish oil highly enriched with docosahexaenoic acid (DHA) by an innovative process termed electrospraying assisted by pressurized gas (EAPG). This technology combines high electric voltage with pneumatic spray to yield a high-throughput encapsulation process. Semi-spherical zein flowable capsules with mean sizes of 1.4 μm containing the DHA-enriched fish oil were produced by EAPG from inert ethanol solutions at room conditions, presenting a high encapsulation efficiency. The oxidative stability tests carried out in the zein microcapsules obtained by EAPG showed that the DHA-enriched fish oil was efficiently protected over storage time. Sensory tests were also performed on fortified reconstituted milk with the freshly prepared zein/DHA-enriched fish oil microcapsules, suggesting negligible oxidation effects after 45 days. The results described herein indicate that EAPG is a promising innovative high-throughput electrospraying-based methodology for the encapsulation of bioactives and, therefore, the resultant DHA-enriched fish oil containing microcapsules can be industrially applied for the formulation of fortified foods. Industrial relevance An innovative process, termed electrospraying assisted by pressurized gas (EAPG), is herein originally presented as a novel encapsulation methodology. This technology is based on the combination of high voltage and pneumatic spray, allowing the formation of microcapsules at room temperature conditions. Thus, EAPG shows a great deal of potential to encapsulate nutraceuticals and other bioactives that are sensitive to thermal degradation and/or oxidation. The resultant bioactive-containing capsules can be, thereafter, applied to develop novel fortified food products.
Production of a β-d-glucan-rich extract from Shiitake mushrooms (Lentinula edodes) by an extraction/microfiltration/reverse osmosis (nanofiltration) process Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-04-06 Diego Morales, Fhernanda Ribeiro Smiderle, Adriana Jimenez Piris, Cristina Soler-Rivas, Marin Prodanov
A pilot-scale process combining extraction of Shiitake mushroom (Lentinula edodes) powder in water (98 °C, 1 h), cross-flow microfiltration and reverse osmosis (nanofiltration) was performed to obtain β-glucan-rich extracts. Suspensions (45–80 L) obtained after 3 extractions were clarified by microfiltration reducing their turbidity to <1 NTU. Membrane flux was completely recovered after filtration. One of the clarified extracts was concentrated (to 6–7 L) by reverse osmosis (Nanomax95) and the other two by nanofiltration (Nanomax50 and ALNF99-2517). Different physicochemical parameters (permeate flux, total soluble substances, total suspended particles and electrical conductivity) were monitored during filtration and the bioactive compounds present in the obtained fractions (β-glucans, total carbohydrates, chitins, eritadenine, lenthionine, ergosterol) were analyzed. The more adequate membrane for Shiitake extract concentration was Nanomax50 because it showed higher filtration flux and higher values of bioactive compounds in the obtained extract than the extracts obtained with the other two membranes. Industrial relevance This work describes a pilot-scale procedure for obtaining β-d-glucan-rich extracts from Lentinula edodes (Shiitake mushrooms). The extracts might be used in novel functional foods due to their high content in hypocholesterolemic compounds. The process combines extraction with boiling water, cross-flow membrane clarification and reverse osmosis/nanofiltration concentration of β-d-glucans. The procedure is scalable to industrial level.
Resistance changes in Salmonella enterica serovar Typhimurium treated by High Hydrostatic Pressure and Pulsed Electric Fields and assessment of virulence changes by using Caenorhabditis elegans as a test organism Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-04-05 Maria Sanz-Puig, Adriana Velázquez-Moreira, Clara Torres, Jose Ángel Guerrero-Beltrán, Luis Miguel Cunha, Antonio Martinez, Dolores Rodrigo
The goal of this study was to evaluate the development of Salmonella enterica subsp. enterica serovar Typhimurium resistance against Pulsed Electric Fields (PEF) and High Hydrostatic Pressure (HHP), and to study the possible virulence changes of the resistant subpopulations using Caenorhabditis elegans. Results showed that S. Typhimurium became resistant to both non-thermal technologies after four consecutive treatments. Survival probability of the worms (C. elegans) increased significantly when they were fed with S. Typhimurium treated by PEF four consecutive times in comparison with the other two subpopulations, untreated and treated once. For HHP, results indicated that up to percentile 50%, the survival probability of worms fed with treated microorganisms (once and four times) was greater than that of worms fed with untreated ones. Also, the C. elegans egg-laying pattern was modified and there were significant differences in the number of eggs laid in the first two days among the three subpopulations studied. Consequently, although S. Typhimurium develops microbial resistance against PEF or HHP treatments, when it is applied repeatedly, its virulence against C. elegans appears to decrease. Industrial relevance Among the non-thermal technologies, Pulsed Electric Fields and High Hydrostatic Pressure have a great potential. Nevertheless, it is necessary to validate them from a safety point of view because of the huge amount of damaged cells that can be obtained if sublethal treatments are applied. These studies have industrial relevance in food safety ensuring proper processing when using these non-thermal technologies.
Coaxial electrospraying of biopolymers as a strategy to improve protection of bioactive food ingredients Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-03-27 Laura G. Gómez-Mascaraque, Fran Tordera, Maria Jose Fabra, Marta Martínez-Sanz, Amparo Lopez-Rubio
Coaxial electrospraying is a promising technique for the production of multilayer encapsulation structures whose potential has already been demonstrated for pharmaceutical and biomedical applications. The aim of this work was to extend its application to the food sector by developing novel coaxially electrosprayed microcapsules using all food-grade materials. For this purpose, zein and gelatin were used as shell biopolymers to microencapsulate two model bioactive ingredients, i.e. epigallocatechin gallate (EGCG) as a model hydrophilic compound and α-linolenic acid (ALA) as a model hydrophobic molecule. The performance of the coaxially-obtained particles in terms of protection was evaluated in comparison with that of uniaxially electrosprayed materials. Particle sizes varied with composition and encapsulation efficiency (EE) was dependent on the chemical affinity between the shell matrix and the bioactive compound, but in general, greater EE was obtained in the coaxial systems. Moreover, enhanced bioactive protection ability was demonstrated by the coaxial structures, as observed in thermal degradation assays (for ALA) and antioxidant activity after in-vitro digestion (for EGCG). Industrial relevance This work emphasizes the usefulness of the electrospraying technique for the production of encapsulation structures for bioactive protection using all food-grade materials, without the need of applying high temperatures and generating small capsule sizes (in the submicron range). It also demonstrates that the coaxial configuration may be used to design encapsulation systems with enhanced protection ability for both hydrophilic and hydrophobic bioactive compounds.
Insects as ingredients for bakery goods. A comparison study of H. illucens, A. domestica and T. molitor flours Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-03-21 Cristina M. González, Raquel Garzón, Cristina M. Rosell
Due to a rising demand for proteins, food industry is considering new alternative protein sources that can be used for human food. The aim of this research was to explore the potential use of insects' flour as protein-rich ingredient for bakery products. Hermetia illucens, Acheta domestica and Tenebrio molitor were ground and used to replace 5% wheat flour in doughs and breads. The protein content of the insect flours ranged from 45% to 57% (d.m.) and fat content from 27% to 36% (d.m.). The inclusion of insects' flour affected the rheological properties (water absorption and stability), of dough during mixing, having less water adsorption. Breadmaking process could be carried out with all the composite flours. Breads containing A. domestica flour showed similar specific volume and texture parameters than wheat bread, but with higher content of proteins and fibers. Globally, results confirmed the usefulness of insects' flour for making breads with improved nutritional value. Industrial relevance This study evaluated the potential application of three different insects as protein source ingredients for bakery products. Results confirm that insects flour could be added to replace wheat flour in breads without significantly affecting dough properties and leading to breads with acceptable technological quality and improved nutritional profile.
Short term evolution of nutritionally relevant milk fatty acids of goats fed a cereal-based concentrate enriched with linseed oil Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-03-19 Pilar Gómez-Cortés, Alfonso Cívico, Miguel Angel de la Fuente, Nieves Núñez Sánchez, Francisco Peña Blanco, Andrés L. Martínez Marín
Goat diet supplementation with linseed oil (LO) can be a fruitful technological strategy to enhance the nutritional value of milk fat. The objective of the present study was to determine the effect of LO in a basal diet rich in starch on goat milk fatty acid (FA) profile. The FA contents were monitored exhaustively during 24 h after LO supplementation or elimination by gas chromatography. Rumenic acid, the main conjugated linoleic acid isomer and α-linolenic acid, both related with bioactive properties, significantly rose in milk between 12 and 24 h after the inclusion of LO in the diet. On the contrary, medium-chain saturated FA decreased. Changes in other nutritionally relevant milk FA as well as short term effects caused by dietary LO suppression are discussed. Industrial relevance Fortification of livestock feeds with lipid supplements is a technological approach that has attracted growing attention in order to change milk fatty acid (FA) profile. Enrichment of ruminant diets with linseed oil (LO) increases omega-3 FA and conjugated linoleic acid as well as decreases saturated FA in milk fat, which improves the nutritional value of dairy products. The present study explores the timing of those changes in the first 24 h after LO inclusion or suppression in the diet. We observed that changes of goat milk fat composition occurred for the most part between 12 and 24 h of LO supplementation, while those changes disappeared between 6 and 12 h after LO suppression. These results would be relevant for producers and industrialists in order to establish appropriate milk collection periods which provide an improved FA profile due to LO supplementation.
Fermentation of commercial soy beverages with lactobacilli and bifidobacteria strains featuring high β-glucosidase activity Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-03-16 Susana Delgado, Lucía Guadamuro, Ana Belén Flórez, Lucía Vázquez, Baltasar Mayo
An increase of isoflavone aglycone content in soy foods can be attained through fermentation with food-grade bacteria. In this study, two commercial soy beverages with distinctive chemical composition (AS and VS) were fermented by strains of lactobacilli (eight strains) and bifidobacteria (two strains) with a high β-glucosidase activity. Along fermentation, growth of the strains and isoflavone deglycosylation in the soy beverages were monitored. Large differences in growth, aglycone content and chemical parameters in AS and VS beverages fermented by different species and strains were observed. Isoflavone glycosides were completely transformed into their corresponding aglycones by most strains during fermentation of AS beverage, whereas large amounts of undeglycosilated isoflavones were still present in fermented VS. Four strains showing strong deglycosylation activity and appropriate technological properties (Lactobacillus casei LP71, Lactobacillus plantarum E112, Lactobacillus rhamnosus E41 and Bifidobacterium pseudocatenulatum C35) were proposed as industrial starters to improve functionality in soy-based fermented foods.
Enrichment in phenolic compounds of black ripe olives through nano-filtration and vacuum evaporation techniques Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-03-08 Pedro García-Serrano, Concepción Romero, Manuel Brenes, Pedro García-García
The aim of this work was to obtain ripe olives enriched in bioactive compounds of phenolic nature. For this, two partially purified solutions rich in phenols from the table olive processes were used as cover in the packaging: washing waters of Spanish-style green olives or previous preservation acid solutions of ripe olives. Both solutions were nano-filtered through a 4000 Da membrane and vacuum evaporated at pilot plant scale. Regenerated liquids were employed at 50% and 100% in the packing brine. Results demonstrated that it is possible to achieve a >3-fold higher concentration of phenolic compounds in olives than with the traditional method when using the regenerated washing water at 100% to enrich the packing brine. Moreover, a <2-fold higher concentration was found in olives enriched with the regenerated preservation solution at 100%. It must also be noted that the color, texture and flavor of the olives were not affected by the use of regenerated washing water as packing solution. Industrial relevance Among the different types of commercial table olives, black ripe have the lowest content in phenolic compounds. The methodology developed in this work will allow the enrichment of black olives in these bioactive substances, in particular hydroxytyrosol, which has been attributed to many beneficial properties for human health. The methodology is simple and easy to implement by processors. Hence, these results will contribute to the nutritional valorization of black ripe olives.
Sanitizing food contact surfaces by the use of essential oils Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-02-14 I. Falcó, M. Verdeguer, R. Aznar, G. Sánchez, W. Randazzo
Chemical sanitizers continue to be widely used by the food industry to disinfect food contact surfaces. However, as some chemical disinfectants have been reported to produce unhealthy by-products, alternative and natural compounds need to be investigated. To this end, nine essential oils (EOs) were screened to develop a natural sanitizing solution (SAN) for disinfecting food contact surfaces. Once extracted, their antimicrobial activity and chemical composition were determined. An exploratory multivariate approach was used to investigate the relationships between the chemical and microbiological data sets. Among the tested EOs, Thymbra capitata EO, containing up to 93.31% oxygenated monoterpenes (mainly carvacrol), showed the strongest antimicrobial activity and thus was assayed as a potential SAN for food contact surfaces. To this end, a SAN consisting of 1% T. capitata EO was first validated according to the AOAC standard, which showed about 8 log reduction for Escherichia coli and Salmonella enterica after 30 and 60 s of contact time, respectively. Then, the SAN was evaluated at various concentrations, cleanliness conditions, and contact times on stainless steel, glass, and polypropylene surfaces for sanitizing purposes. The results showed that the SAN containing 2.5% of T. capitata EO applied for 10 min, reduced the levels of E. coli by >3 log and S. enterica by 1 log under clean working conditions on the three tested surfaces. These findings indicate that EOs can be used as natural disinfectants to decontaminate food contact surfaces, thus lowering the risk of the indirect transfer of bacterial pathogens to food or persons.
Simultaneous saccharification and cultivation of Candida utilis on cassava peel Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-02-13 Olufunke Ezekiel, Ogugua Aworh
Candida utilis yeast, a rich source of proteins and vitamin B-complex was cultivated on cassava peel, a food processing waste, which was first liquefied with Termamyl 120 L α-amylase enzyme. The cultivation process was optimized simultaneously with saccharification with Novo AMG 300 L amyloglucosidase using response surface methodology approach. The design involved three duration of enzyme hydrolysis (0, 4.5 and 9 h) prior to inoculation with Candida utilis representing varied degrees of hydrolysis (0, 50 and 100%) and initial pH (4.5, 5.0 and 5.5). Measured responses were change in yeast protein ranging from 1.13 to 1.91 mg/mL, change in cell concentration ranging from 2.30 to 3.90 mg/mL and specific growth rate ranging from 0.21–0.51.100% hydrolysis and initial pH of 5.0 gave the highest changes in yeast protein (1.92 mg/mL) and cell concentration (3.90 mg/mL); 100% hydrolysis and pH 5.5 gave the highest specific growth rate. The optimal solution was obtained at pH of 5.5 and 100% degree of hydrolysis with a degree of desirability of 0.8. The cultivation of Candida utilis yeast on cassava peel is of high significance to food and agro-based industries for the production of value added products, waste disposal and valorisation. Industrial relevance Cassava peel is a major waste product from cassava processing industry which is faced with an enormous challenge regarding its disposal. This study revealed that Candida utilis can be cultivated successfully on cassava peel slurry; the cultivation of this yeast on cassava peel is of high significance to food and agro-based industries for the production of value added products waste disposal and valorisation.
Mechanism characterization of bacterial inactivation of atmospheric air plasma gas and activated water using bioluminescence technology Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-02-02 Shyam Suwal, Claudia P. Coronel-Aguilera, Jameson Auer, Bruce Applegate, Allen L. Garner, Jen-Yi Huang
We assessed the efficacy of bacterial inactivation using a dielectric barrier discharge in three different plasma setups: plasma gas (PG), and direct and indirect plasma activated water (PAW), where deionized water was placed either between or away from the electrodes, respectively. We used bioluminescent Escherichia coli K12 lux as a model bacteria in a biosensor format to study the inactivation kinetics and mechanism of action of produced PG and PAW. The results showed that uninterrupted application of PG decreased bioluminescence rapidly by 1-log within the first minute and 3.6-log after 10 min of treatment. Exposing the bacterial culture with a sublethal dose of PAW (1 mL) rapidly decreased the bioluminescence; however, luminescence slowly recovered after exposure. Subsequent treatment with PAW decreased the bioluminescence to a lesser extent. In addition, direct PAW induced a greater decrease in bioluminescence compared to indirect treatments for both single and multiple exposures. In contrast to the PG, PAW treatments induced a lower bactericidal effect with 0.11 to 0.22-log reduction for indirect PAW and 0.2 to 0.32-log for direct PAW. Our results also indicate that antimicrobial activity of PAW decreased slowly within 20 min of its preparation. The rapid decrease in bioluminescence followed by a partial recovery in a repeatable pattern suggests an incomplete inactivation, and that the reducing power of the cell helps them to survive. Moreover, the complete and partial oxidation of NADH solutions in vitro by PG and PAW, respectively, strongly suggest that the lux fluorophore FMNH2 and other reducing cofactors could be the target of such treatment before other cell components. This hypothesis was supported by the tendency to recover luminescence by potentially replenishing the pool of FMNH2 after plasma treatment. It is also important to consider that the reducing power of the cell (NADH, NADPH, and FMNH2) is crucial for cell viability mostly due to reducing potential for critical metabolic reactions. Therefore, in situ bioluminescence monitoring technology can potentially serve as a unique approach to elucidate the mechanism of bacteria inactivation in real time. Industrial relevance The present study developed three dielectric barrier discharge (DBD) plasma setups to produce plasma gas and plasma activated water, which can disinfect both food products and their contact surfaces regardless of geometry. Our in situ bioluminescent technology elucidated bacterial inactivation mechanisms of plasma treatments, which may potentially suggest sufficient exposures to plasma resulting in safe food products without deteriorating their quality. The results will help food manufacturers apply new plasma-based disinfection methods with appropriate treatments.
The impact of steam-blanching and dehydration on phenolic, organic acid composition, and total carotenoids in celery roots Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-01-31 Liga Priecina, Daina Karklina, Tatjana Kince
From the nutritional point of view, studying thermal and non-thermal processing effects is highly important for various nutrients which include numerous biologically active components in vegetables used daily. Therefore, the aim of current research was to study steam-blanching (at 1.5 and 3.0 min), convective drying, microwave-vacuum (MV) drying and then calculate the effect each had on individual organic acids, individual phenolic compounds, total phenolics, antiradical activity of phenolic compounds and colour within the celery roots. Fresh celery roots contain a trace amount of carotenoids which decreases significantly during drying. Total phenolic content in fresh celeries was determined in lower concentrations than flavonoids and during drying process their content increases. It was determined that celery roots dried with the convective method contained higher total phenolic content than those dried with the MV method, however, the highest flavonoid content was observed in the MV dried root samples which were preheated with steam. The determined individual phenolic compounds in higher amounts were: 3.4-dihydroxybenzoic, 4-hydroxybenzoic, chlorogenic, sinapic and t(3)-cinnamic acids. The determined major organic acids in higher amounts were oxalic, malonic, citric, ascorbic and succinic acids.
Effects of drying methods on total phenolic contents and antioxidant capacity of the pomelo (Citrus grandis (L.) Osbeck) peels Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-01-31 Nur Farhana Abd Rahman, Rosnah Shamsudin, Amin Ismail, Nor Nadiah Abdul Karim Shah, Jaturapatr Varith
Pomelo (Citrus grandis (L.) Osbeck) is an important cultivar of the Citrus genus, which contains a number of nutrients advantageous to human health. Non-edible parts of pomelo consist of flavedo, albedo, lamella and waste obtained from juice extraction (pulp waste). The peels are also thought to be part of waste products, which generally being discarded. Therefore, the objective of the present study was to evaluate changes in total phenolic contents (TPC) and antioxidant activity of processed pomelo peels after oven drying (50 and 60 °C) and freeze drying treatments in comparison with fresh pomelo peels. A slightly different (4%–6%) in TPC was observed in oven dried pomelo peels in comparison with fresh peels, indicating that there was a slightly effect of post-drying methods on retaining the antioxidant potential of these natural byproducts. In vitro assays revealed that post-drying methods involved oven drying exerted a higher TPC compared to freeze drying in overall parts of pomelo byproducts. Highest retention of bioactive compounds was found in fresh pomelo peels (437–1876 mg GAE/100 g DM), followed by oven dried at 50 and 60 °C (892–1336 mg GAE/100 g DM), and freeze dried (555–1267 mg GAE/100 g DM). In terms of oven dried pomelo byproducts, the highest TPC was retained in albedo (1337 mg GAE/100 g DW), followed by flavedo (1226 mg GAE/100 g DW), lamella (998 mg GAE/100 g DW) and pulp waste (962 mg GAE/100 g DW) respectively. Therefore, oven drying was the most suitable post-drying method to retain the bioactive compounds for pomelo byproducts. This knowledge may inspire consumer or pomelo industry operators to re-evaluate their byproducts, reduce the waste and expand the application of pomelo fruits. Industrial relevance Non-edible of pomelo fruits are thought as a part of waste products which generally being discarded. Interestingly, it was found that the peel have higher phenolic contents and antioxidant potentials than the pulps. However, processing involves drying process diminishes the product quality due to the deviations in quantity and feature of thermolabile phytochemicals. The objective of this work was to assess variations in total phenolic contents (TPC) and antioxidant behavior of processed pomelo peels during post drying treatments. The information reported here may encourage pomelo industry operators to re-evaluate their by-products, extending the application of pomelo fruits and reducing waste. As natural products, with apparent antioxidant capacity, processed pomelo residues look very promising for use in development of functional and nutraceutical applications.
Physical properties of 3D printed baking dough as affected by different compositions Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2018-01-05 Fan Yang, Min Zhang, Sangeeta Prakash, Yaping Liu
Gel formation characteristics and physical properties of baking dough changes with different composition of water, sucrose, butter, flour and egg contents. This study aims to explore how these changes affect 3D printing of the dough through laser scanning confocal microscopy (LSCM), low-field nuclear magnetic resonance (NMR), torque rheometer and texture analyser. Results show a pseudoplastic gel with suitable level of physical properties such as relatively higher extrudability, gel strength, elasticity and relatively lower ductibility was required to obtain better shape of the extruded samples. In conclusion, the best shape of 3D printing baking dough which was retained with proper gel formation characteristics and physical properties was obtained with a recipe containing water (29 g), sucrose (6.6 g), butter (6.0 g), flour (48 g) and egg (10.4 g) per 100 g of formulation. Industrial relevance The formulation of baking dough affected the modeling quality of printed samples. Thus, the optimized formulation of modified baking dough will contribute to the success in practical production.
Sanitation of fresh-cut endive lettuce by plasma processed tap water (PPtW) – Up-scaling to industrial level Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2017-12-09 Uta Schnabel, Mathias Andrasch, Jörg Stachowiak, Christoph Weit, Thomas Weihe, Christian Schmidt, Peter Muranyi, Oliver Schlüter, Jörg Ehlbeck
The decontamination and sanitation methods currently used are mainly antimicrobial ineffective, generate high costs with a high consumption of water and chemicals (additives). As an alternative, non-thermal plasma at atmospheric pressure could be a versatile tool. Therefore, a pilot-scaled set-up based on a microwave-plasma source that generates plasma processed air (PPA), a gaseous mixture which contains manifold RNS-based chemical compounds gaining, among others, the antimicrobial effectivity of that mixture. The PPA was introduced to a water-processing device (WPD) to enrich tap water. By this way, plasma processed tap water (PPtW), which can be applied for the decontamination of packaging material, fresh produce and processing equipment, was generated. This is a new and innovative method for the generation of antimicrobial active plasma processed water. In our experiments, the native contamination of fresh-cut lettuce treated with PPtW in a common washing process and the microbial load of the washing water itself was investigated. Different treatment scenarios showed the influence of PPtW to the fresh-cut lettuce and the washing water as well as the hygienic problems of recontamination during the washing process. The characteristics of plasma and its generated cocktail of long living chemical compounds in air and in water leading to a significant bacterial inactivation and offering a wide range of possible applications. Industrial relevance The safety, quality and shelf life of freshly cut vegetables greatly depend on the microbial load, especially with phyto and human pathogens, of the produce as well as the hygienic design of production device and good handling and production practice. This study shows that the application of PPW/PPtW, as a promising non-thermal sanitation technology, enables the inactivation of native contamination on fresh-cut lettuce in industrial relevant level. It further describes the impact of the necessity of hygienic environment during production to avoid cross- and re-contamination. The results contribute to the understanding and product-specificity of PPW-induced effects on safety, quality and shelf life of fresh cut lettuce and could be a basis for a possible industrial implementation and complement of common technologies.
Improvement of fatty acid profile in breads supplemented with Kinako flour and chia seed Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2017-11-15 D. Giaretta, V.A. Lima, S.T. Carpes
Breads with functional ingredients can be a healthier alternative to a low-saturated fatty acid diet. The effects of the substitution of wheat flour with kinako flour and chia seed (Salvia hispanica L.) on the fatty acid profile of bread, were investigated. With the aim of improving the nutritional quality of the breads, the fatty acid profile of soybean, kinako, chia and breads, were evaluated by gas chromatography. In these food matrices, six fatty acids were detected; the most expressive ones were linoleic, oleic, palmitic and linolenic acids. The highest polyunsaturated fatty acid (PUFA) amounts were achieved for the chia seed and the linolenic acid was predominant. The PUFA amount was higher than 63% and the major component was linoleic acid; 53.81 and 55.95 mg/100 g of total lipids in the soybean seeds and kinako flour, respectively. The addition of kinako flour and chia seed to bread resulted in a reduction in SFA and MUFA content and a significant increase in the content of PUFA. Furthermore, a lower n-6/n-3 ratio was obtained in special breads that had an addition of kinako flour and chia. Intrinsic characteristics of these food matrices can improve the quality of breads and can bring health benefits to the consumer.
Impact of magnetic assisted freezing in the physicochemical and functional properties of egg components. Part 2: Egg yolk Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2017-11-14 F. Fernández-Martín, M. Pérez-Mateos, S. Dadashi, C.M. Gómez-Guillén, P.D. Sanz
Effects of freezing assisted with magnetic fields (MFs) in a commercial Cell Alive System (CAS) unit at − 50 °C, with a static MF only (0% CAS) and with a static MF plus oscillating MF (10% CAS), on egg yolk (Y) was investigated. Y samples were obtained from commercial eggs laid by three hen strains (two of them in fortified cages and the third one free outdoors). The main goal was to study the thermal denaturation of protein involved in MF processing. Results showed that freezing treatment was the factor with the highest influence. Thermal denaturation enthalpy of Y was markedly affected (~ 45% total protein in comparison with Fresh sample), but similar for the two MF processes, where 0% CAS was taken as the Control freezing treatment. MF effects were predominantly thermal in nature and were the factor with the highest influence on the thermal behavior (which ran parallel to that of egg white, as described in Part 1), as well as on most of the functional properties exhibited by the MF samples. Rheology and free Sulfhydryl content were studied complementarily to Differential Scanning Calorimetry (DSC) data. Some important functional properties such as Emulsion Ability and Emulsion Stability were also determined. The hen strain feeding factor had practically no influence on the physical or functional behavior of both untreated and processed Y samples, except on their color parameters.
Influence of partial pressure of oxygen on ascorbic acid degradation at canning temperature Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2017-11-13 Nizar Al Fata, Stéphane Georgé, Naïma Dlalah, Catherine M.G.C. Renard
Oxygen is known to be one of the major causes of oxidative degradations of nutrients. Ascorbic acid, a component of interest due to its health benefits, is reported to be highly oxygen sensitive. To understand better the influence of oxygen on ascorbic acid retention at canning temperature, thermal treatment was performed in model solution at pH = 3.5 with varying partial pressure of oxygen from 0 MPa (strict anaerobic conditions) to 0.1 MPa in the headspace gas, from 95 °C to 125 °C, starting from an initial concentration of 900 mg/L. Treatment of 320 min was not sufficient to completely degrade all ascorbic acid initially present in the medium under anaerobic conditions and with a partial pressure of oxygen in headspace at 0.03 MPa, but treatment of 120 min was sufficient to degrade all initial ascorbic acid when the partial pressure of oxygen in headspace was set at 0.1 MPa. Apparent reaction orders were calculated; they were of 1 under anaerobic conditions, and 0.5 or 0.75 depending on partial pressure of oxygen. Activation energy was calculated using the Arrhenius law under anaerobic conditions only (Ea = 67 kJ/mol). When oxygen is present, whichever its partial pressure in headspace, no acceleration of reaction was observed with increased temperature.
The impact of high voltage electrical discharge plasma on the chromatic characteristics and phenolic composition of red and white wines Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2017-11-10 Katarina Lukić, Tomislava Vukušić, Marina Tomašević, Natka Ćurko, Leo Gracin, Karin Kovačević Ganić
The cold plasma is an emerging electrotechnology for the improvement of food safety without loss of physicochemical or sensory properties. The purpose of this study was to evaluate the effects of plasma treatments on the chromatic characteristics and phenolic composition of red and white wines. The red wine Cabernet Sauvignon and white wine Graševina were treated with high voltage electrical discharge plasma considering the variations in frequency (60, 90 and 120 Hz) and processing time (3, 5 and 10 min). Total phenolics, total anthocyanins, total tannins and chromatic characteristics were analyzed by spectrophotometry while free anthocyanins, phenolic acids and flavan-3-ols by the HPLC-UV/Vis. Obtained results illustrated that plasma treatments have influenced the stability of phenolic compounds in wines without major changes in color parameters. Also, among two different processing parameters, the duration time was the most significant factor inducing changes on wines. Industrial relevance High voltage electrical discharge plasma has been shown to affect the stability of wine phenols without any significant change in the color. An increase in the concentration of certain phenolic compounds in white wine suggest that this technique could be used in the wine industry as an alternative technique for enhancing the oxidative stability of wine and consequently the wine quality during the aging process.
An untargeted chemometric evaluation of plasma and ozone processing effect on volatile compounds in orange juice Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2017-10-03 E.G. Alves Filho, T.H.S. Rodrigues, F.A.N. Fernandes, E.S. de Brito, P.J. Cullen, J.M. Frias, P. Bourke, R.S. Cavalcante, F.D.L. Almeida, S. Rodrigues
The study of small molecules based on “fingerprint” approaches and non-target methodologies has been used to understand changes caused during natural or industrial processes. In this work, chemometrics was applied to evaluate changes according to the volatile composition of orange juice subjected to ozone and plasma processing, and its influence on the flavor compounds of the juice. HS-SPME-GC/MS analysis was able to differentiate the juices processed by ozone and plasma, mainly showing the oxidation of limonene, y-terpinene, and linalool to the orange off-flavor components α-terpineol and terpinen-4-ol, the formation of decanal, and the degradation of p-cymene. The multivariate chemical analysis of volatile compounds of orange juice indicated a significant difference between juices treated with short-period ozone treatment (1 to 3 min) and using long-period ozone treatment and plasma treatment.
Shelf-life extension of herring (Clupea harengus) using in-package atmospheric plasma technology Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2017-09-17 I. Albertos, A.B. Martin-Diana, P.J. Cullen, B.K. Tiwari, K. Shikha Ojha, P. Bourke, D. Rico
Atmospheric cold plasma is a green and emerging technology, highly interesting to the food industry for its application. Dielectric Barrier Discharges (DBD) can generate atmospheric cold plasma inside sealed packages filled with air through the use of high voltages. This study investigated the use of a large gap DBD design to generate a plasma discharge within the headspace of packaged herring fillets, and its effects on microbiological and quality markers of the fish stored for 11 days at 4 °C. DBD plasma treatment conditions were 70 kV or 80 kV for 5 min treatment time. Results showed that the microbial load (total aerobic mesophilic, total aerobic psychrotrophics, Pseudomonas, lactic acid bacteria and Enterobacteriaceae) were significantly (p < 0.05) lower in the treated samples compared to the control samples. However, samples exposed to the lowest applied voltage better retained key quality factors (lower oxidation and less colour modification). DBD-treatment caused a reduction in trapped water in the myofibrillar network (T21), identified using low-field nuclear magnetic resonance of protons (1H LF NMR). The results indicate that in-package plasma treatment could be employed as an effective treatment for reducing spoilage bacteria in fish. Industrial relevance Dielectric Barrier Discharge (DBD) was evaluated as a treatment for highly perishable fish products. DBD's is a safety and lower costs alternative for processing industry. DBD has been scarcely tested on fish; this work showed results on quality and shelf-life of a highly perishable fish species, which might serve as reference for processing optimisation of fish products minimally processed by DBD.
Color development, physiochemical properties, and microbiological safety of pork jerky processed with atmospheric pressure plasma Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2017-09-15 Hae In Yong, Sang Hui Lee, So Yeon Kim, Sanghoo Park, Jooyoung Park, Wonho Choe, Cheorun Jo
We investigated the applicability of atmospheric pressure plasma (APP) as an alternative to sodium nitrite in pork jerky manufacturing. Pork slices were marinated in brine with no sodium nitrite at 4 °C for 16 h and treated by APP for 0, 20, 40, and 60 min, respectively. The sample marinated in the brine with sodium nitrite (100 ppm) was also prepared. Then, all samples were dried. As APP treatment time increased, the a⁎ value (redness), nitrosoheme pigment content, and residual nitrite content increased, while lipid oxidation decreased (all P < 0.05). Similar quality properties, particularly color, were observed in jerky applied by APP for 40 min compared to jerky made with sodium nitrite. After inoculation of marinated pork with Staphylococcus aureus or Bacillus cereus, the amounts of both pathogens in jerky applied by APP for 40 and 60 min were significantly lower than in jerky made with sodium nitrite. Consequently, APP can be applied for manufacturing potentially safer pork jerky without added sodium nitrite. Industrial relevance The global interest in sodium nitrite substitute for meat products manufacturing has considerably grown for years because consumer's demand of foods labeled “natural” and “chemical-free” has been increasing. In general, APP is recognized as a novel non-thermal food processing technology that uses energetic, reactive species to inactivate microbes on various foods. Recently, meat curing system involving direct APP treatment was proposed. The present study tried to apply APP to manufacturing pork jerky without using sodium nitrite. As a result, similar quality properties, particularly color, were observed in jerky applied by APP compared to jerky made with sodium nitrite. Application of APP also improved the microbiological safety of pork jerky. Therefore, APP can be applied for manufacturing potentially safer pork jerky by inactivation of heat-resistant pathogens without added sodium nitrite.
Browning response of fresh-cut apples of different cultivars to cold gas plasma treatment Innov. Food Sci. Emerg. Technol. (IF 3.116) Pub Date : 2017-08-12 Silvia Tappi, Luigi Ragni, Urszula Tylewicz, Santina Romani, Ileana Ramazzina, Pietro Rocculi
The present work aims to study the effects of cold gas plasma on some quality parameters of apple slices belonging to four different cultivars (Pink Lady®, Fuji, Red Delicious and Modì®), with particular attention to polyphenoloxidase (PPO) inhibition and related changes in colour and visual quality. Upon plasma exposure a noticeable reduction of superficial browning was observed in all cultivars but not always proportionally to treatment time; the effect on PPO activity was very variable and not correlated to the effect on enzymatic browning. Textural parameters were affected by plasma treatments only in Red Delicious apples. Generally, the response of the tissue to the treatments was variable according to the cultivar considered. The results obtained in this study indicate the necessity of further investigation about consequences of plasma treatment on specific tissue physiology in order to choose the better treatment parameters, optimizing its effect for the specific final product. Industrial relevance The application on cold plasma to minimally processed fruit and vegetable has shown a good potential for enzymatic browning inhibition making it an interesting alternative to traditional dipping methods. Nevertheless, the effect on the tissue to the exposure to plasma active particles is not fully known yet. For the industrial application of the treatment, the response for example of different cultivars to the treatment is of high importance, in the first place for the selection of the more appropriate raw material but also to eventually adapt the process parameters to the specificity of the matrix.
Some contents have been Reproduced by permission of The Royal Society of Chemistry.
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