Skip to main content
Log in

Experimental investigations and modeling of vacuum oven process using several semi-empirical models and a fuzzy model of cocoa beans

  • Original
  • Published:
Heat and Mass Transfer Aims and scope Submit manuscript

Abstract

An experimental study combined with a mathematical modeling of vacuum drying of cocoa beans was carried out to enhance the drying kinetics without compromising the quality of dried products. Experiments were conducted to compare the effects of variation of temperature and pressure on the drying process. The temperature was varied between 40 and 60 °C, while the pressure between 735 and 245 mmHg. The experimental study investigated and analyzed the effects of various process parameters on drying kinetics and quality (in terms of color and pH value). Results demonstrated that the cocoa beans dried at 50 °C temperature and 735 mmHg pressure had the highest drying kinetics, lowest acidity, and best color among all the temperature and pressure values. Compared to convective drying conducted at 60 °C temperature and atmospheric pressure (760 mmHg), vacuum oven drying consistently showed better drying performance with a higher quality of dried products. Modeling for vacuum drying kinetics of cocoa beans was performed with semi-theoretical drying kinetic and fuzzy models to verify the experimental results. The graphical representations of the results demonstrated a good fit between the fuzzy model and the experimental data compared with semi-theoretical drying kinetic models. Finally, a suitable model was proposed for optimum drying conditions compared with the fuzzy and drying kinetic models that could play an important role in designing future advanced dryers.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10

Similar content being viewed by others

Abbreviations

Deff:

Effective moisture diffusivity, m2/s

g:

Constant in the two term and Verma et al. models, s−1

g:

Constant in the C.L. Hii model, s−1

k:

Constant in the Newton, Henderson and Pabis, logarithmic, two term, and Verma et al. models, s−1

k:

Constant in the page and C.L. Hii models, s−n

K:

Thermal diffusivity, m2/s

L, a, b:

Reference color (lightness, redness and yellowness, respectively),

L*, a*, b*:

Target color (lightness, redness and yellowness, respectively),

mt:

Mass of sample at time t, g

mds:

Mass of dry solid, g

Me:

Equilibrium moisture content (dry basis), kg/kg

M0:

Initial moisture content (dry basis), kg/kg

Mt:

Moisture content at time t (dry basis), kg/kg

MR:

Moisture ratio,

pH:

Acidity/basicity,

P:

Pressure, mm Hg

R2 :

Coefficient of determination, −

T:

Temperature, °C

ΔE:

Change of color,

COG:

Center of gravity

FL:

Fuzzy logic

MF:

Membership function

MSE:

Mean square error

RMSE:

Root mean square error

SC:

Subtractive clustering

TSK:

Takagi-Sugeno-Kang

References

  1. Aamilla G, Cervantes S, Barel MA, Berthmieu G, Rodriuges-Jimens GC, Garcia-Alvarado MA (2007) Moisture acidity and temperature evolution during cacao drying. J Food Eng 79:1159–1165

    Article  Google Scholar 

  2. Akmel DC, Assidjo NE, Kouamé P, Yao KB (2019) Modelling of sun drying kinetics of thin layer cocoa (Theobroma cacao) beans. J Appl Sci Res 5(9):1110–1116

    Google Scholar 

  3. Camu N, Winter DW, Addo SK, Takrama JS, Bernart H, Vuyst LE (2008) Fermentation of cocoa beans: influence of microbial activities and polyphenol concentrations on the flavor of chocolate. J Sci Food Agricult 88:2288–2297

    Article  Google Scholar 

  4. Chandra PK, Singh RP (1995) Applied numerical methods for food and agricultural engineers. CRC Press, Boca Raton, pp 163–167

    Google Scholar 

  5. Chen Z, Lamb FM (2004) A vacuum drying system for green hardwood parts. Dry Technol 22:577–595

    Article  Google Scholar 

  6. Devahastin S, Mujumdar AS (2008) Fundamental principles of drying. In: Mujumdar A.S. (ed) Guide to industrial drying. Colour Publications Pvt. Limited, India, p 1–19

  7. Guehi TS, Zahouli IB, Ban-Koffi L, Fae MA, Nemlin JG (2010) Performance of different drying methods and their effects on the chemical quality attributes of raw cocoa material. Int J Food Sci Technol 45:1564–1571

    Article  Google Scholar 

  8. Henderson SM, Pabis S (1969) Grain drying theory. I. Temperature effect on drying coefficient. J Agric Eng Res 6:169–174

    Google Scholar 

  9. Hii CL, Law CL, Cloke M (2009) Modelling using a new thin layer drying model and product quality of cocoa. J Food Eng 93:191–198

    Article  Google Scholar 

  10. Hii CL, Law CL, Cloke M, Suzannah S (2009) Thin layer drying kinetics of cocoa and dried product quality. Biosyst Eng 102:153–161

    Article  Google Scholar 

  11. Hii CL, Law CL, Cloke M (2018) Modelling of thin layer drying kinetics of cocoa beans during artificial and natural drying. J Eng Sci Technol 3(1):1–10

    Article  Google Scholar 

  12. Hoque ME, Gee LP (2013) Biodiesel from plant resources – sustainable solution to ever increasing fuel oil demands. J Sustain Bioenergy Syst 3:163–170

    Article  Google Scholar 

  13. Kanagaratnam S, Hoque SE, Sahri MM, Spowage A (2013) Investigating the effect of deforming temperature on the oil-binding capacity of palm oil based shortening. J Food Eng 118(1):90–99

    Article  Google Scholar 

  14. Kuitche A, Edoun M, Takamte G (2007) Influence of pre-treatment on drying on the drying kinetic of a local Okro (Hibiscus ersculentus) variety. World J Dairy Food Sci 2(2):83–88

    Google Scholar 

  15. Kyi TM, Daud WRW, Mohammad AB, Samsudin MW, Kadhum AAH, Talib MZM (2005) The kinetics of polyphenol degradation during the drying of Malaysian cocoa beans. Int J Food Sci Technol 40:323–331

    Article  Google Scholar 

  16. Majdi A-M, Aljarrah M, Rababah T (2016) Application of hybrid neural fuzzy system (ANFIS) in food processing and technology. Food Eng Rev 8(3):351–366

    Article  Google Scholar 

  17. Maskan M (2000) Microwave/air and microwave finish drying of banana. J Food Eng 46:71–78

    Article  Google Scholar 

  18. Mujumdar AS (2006) Innovation and globalization in drying R&D. Proc 15th Int Drying Symp IDS 14:3–17

    Google Scholar 

  19. Nassef AM, Sayed ET, Rezk H, Abdelkareem MA, Rodriguez C, Olabi AG (2018) Fuzzy-modeling with particle warm optimization for enhancing the production of biodiesel from microalga. Energ Source Part A: Recovery Util Environ Effects 41(17):1–10

    Google Scholar 

  20. O’Callaghan JR, Menzies DJ, Bailey PH (1971) Digital simulation of agricultural dryer performance. J Agric Eng Res 16:223–244

    Article  Google Scholar 

  21. Oke DO, Omotayo KF (2012) Effect of forced-air artificial intermittent drying on cocoa beans in South-Western Nigeria. J Cereals Oil Beans 3(1):1–5

    Google Scholar 

  22. Page G (1949) Factors influencing the maximum rates of air-drying shelled corn in thin layers. M.S. Dissertation. Purdue University, Lafayette

    Google Scholar 

  23. Paramo D, Garcia-Alamilla P, Salgado-Cervantes MA, Robles-Olvera VJ, Rodriguez-Jimenes (2010) Mass transfer of water and volatile fatty acids in cocoa beans during drying. J Food Eng 99:276–283

    Article  Google Scholar 

  24. Rahman SMA, Hoque ME, Rahman S, Hasanuzzaman M (2015) Osmotic dehydration of pumpkin using response surface methodology – influences of operating conditions on water loss and solute gain. J Bioprocess Biotech 5:1–6

    Article  Google Scholar 

  25. Rahman SMA, Hoque ME, Rahman S, Rahman MM (2017) A novel vortex tube assisted atmospheric freeze-drying system: effect of osmotic pre- treatment on biological products. J Food Process Eng 40(3):1–11

    Google Scholar 

  26. Saltini R, Akkerman R, Frosch S (2013) Optimizing chocolate production through trace- ability: a review of the influence affirming practices on cocoa bean quality. Food Control 29:167–187

    Article  Google Scholar 

  27. Saravacos GD, Maroulis ZB (2001) Transport properties of foods. Marcel Dekker Inc, New York

    Book  Google Scholar 

  28. Shahpour JR, Mohammad K, Vali RS (2018) Fuzzy logic, artificial neural network and mathematical model for prediction of white mulberry drying kinetics. Heat Mass Transf 54(11):3361–3374

    Article  Google Scholar 

  29. Sharaf-Eldeen YI, Blaisdell JL, Hamdy MY (1980) A model for ear corn drying. Trans ASAE 5:1261–1265

    Article  Google Scholar 

  30. Takagi T, Sugeno M (1985) Fuzzy identification of systems and its applications to modeling and control. IEEE Trans Syst Man Cybern 15:116

    Article  Google Scholar 

  31. Therdthai N, Zhou WBN (2009) Characterization of microwave vacuum drying and hot air drying of mint leaves (Mentha cordifolia Opiz ex Fresen). J Food Eng 91(3):482–489

    Article  Google Scholar 

  32. Verma LR, Bucklin RA, Endan JB, Wratten FT (1985) Effects of drying air parameters on rice drying models. Trans ASAE 28:296–301

    Article  Google Scholar 

  33. Yang T, Yong L, Ruiyun Z, Dinh-Toi C (2016) Neuro-fuzzy modeling to predict physicochemical and microbiological parameters of partially dried cherry tomato during storage: effects on water activity, temperature and storage time. J Food Sci Technol 53(10):3685–3694

    Article  Google Scholar 

Download references

Acknowledgments

The authors would like to thank the University of Sharjah for the financial support to conduct this study (Project no: 1602040652-P). Besides, the authors have the deepest gratitude to Assistant Professor Andrew Joseph Power at the University of Sharjah for his kind proofreading providing beneficial comments that significantly helped to improve the overall quality of this paper. The authors would also like to thank Eng. Salah Issa Elsayed for his technical supports provided during this study.

Funding

This research was funded by The University of Sharjah, 1602040652-P”.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to S. M. Atiqure Rahman.

Ethics declarations

Conflict of interest

There is no conflict of interest.

Additional information

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Rahman, S.M.A., Nassef, A.M., Rezk, H. et al. Experimental investigations and modeling of vacuum oven process using several semi-empirical models and a fuzzy model of cocoa beans. Heat Mass Transfer 57, 175–188 (2021). https://doi.org/10.1007/s00231-020-02943-5

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00231-020-02943-5

Keywords

Navigation