Innovative Food Science & Emerging Technologies ( IF 6.6 ) Pub Date : 2020-03-25 , DOI: 10.1016/j.ifset.2020.102345 S.S. Shirkole , R. Jayabalan , P.P. Sutar
The present study was undertaken for inactivation of S. Typhimurium and A. flavus in paprika by short time intensive microwave-infrared (MW-IR) radiation. The MW-IR heating experiments were carried out using the central composite design with the microwave power density, infrared heater temperature, the distance between the infrared heater and paprika layer, and heating time in the range of 4–12 W g−1, 75–375 °C, 6–14 cm and 15–75 s, respectively. It was observed that whenever the temperature of paprika was exceeded its corresponding glass transition temperature, it resulted in accelerated moisture diffusion and quality degradation. Also, the correlation of overall color degradation with sorption and thermal characteristics of paprika was established. The spatial changes in the temperature and water activity of paprika during short time intensive MW-IR heating resulted in 8.849 log reduction of total plate count (S. Typhimurium) and 7.372 log reduction of yeast and mold count (A. flavus) in presence of natural microbial flora.
Industrial relevance
India is the largest producer, consumer, and exporter of spices in the world. The steam-assisted sterilization is widely practiced in Indian spice industry but steam treatment is problematic particularly for paprika because of moisture condensation and additional drying cycle resulting in excess quality degradation which fetches a low price in the export market. The present work has been carried out based on industry demand for alternative technology considering spice growers and processors with the special requirement on the quality profile, bactericidal efficacy, ease of operations, cost-effectiveness, and affordability. The results of the present study showed that the short time intensive MW-IR assisted heating process would be an alternative method for finish drying, microbial and enzyme inactivation, and restriction of moisture deteriorative reactions in low moisture products like spices considering demand of spice growers, processors, and exporters.
中文翻译:
短时强微波-红外辐射对辣椒粉(辣椒)的干法杀菌作用:第一部分-利用玻璃化转变,吸附和质量降解动力学参数建立工艺
本研究的目的是为灭活小号。鼠伤寒和一个。短时密集的微波红外(MW-IR)辐射在辣椒粉中提取黄酮。使用中央复合设计进行了MW-IR加热实验,微波功率密度,红外加热器温度,红外加热器与辣椒粉层之间的距离以及加热时间为4-12 W g -1分别为75–375°C,6–14 cm和15–75 s。观察到,每当辣椒粉的温度超过其相应的玻璃化转变温度时,都会加速水分扩散并降低质量。此外,还建立了整体颜色降解与辣椒粉的吸附和热特性的相关性。短的时间密集的MW-IR加热期间在辣椒粉的温度和水活度的空间变化导致总平板计数的8.849 log减少(小号。鼠伤寒沙门氏菌)和酵母和霉菌计数(的7.372 log减少阿。黄曲霉)中的存在天然微生物菌群。
行业相关性
印度是世界上最大的香料生产国,消费国和出口国。蒸汽辅助灭菌在印度香料工业中已广泛使用,但是蒸汽处理尤其对辣椒粉有问题,因为水分凝结和额外的干燥周期会导致质量下降,在出口市场上价格低廉。考虑到香料种植者和加工者对质量特征,杀菌效力,操作简便,成本效益和可承受性有特殊要求,目前的工作是基于香料技术的种植者和加工者对替代技术的行业需求而进行的。本研究的结果表明,短时密集的MW-IR辅助加热过程将是完成干燥,微生物和酶失活的另一种方法,