Effects of Different Drying Methods on the Nutrition and Physical Properties of Momordica charantia
DENG YuanYuan;TANG Qin;ZHANG RuiFen;ZHANG Yan;WEI ZhenCheng;LIU Lei;MA YongXuan;ZHANG MingWei;Sericultura & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences/Key Laboratory of Functional Foods,Ministry of Agriculture/Guangdong Key Laboratory of Agricultural Products Processing;
【Objective】The objective of this study is to provide a theoretical basis for choose the optimal industrial production mode of drying process of Momordica charantia L. by studying the effect of different drying methods on nutrition, antioxidant and physical properties. 【Method】Nutrition components(polysaccharide, Vc, total phenolics, total flavonoid, carotenoid), oxygen radical absorbance capacity(ORAC), sensory evaluation(color and hardness) and microstructure were taken as evaluation indices. Vacuum freeze drying(VFD), sun drying(SD), heat pump drying(HPD), heat air drying(HAD), microwave drying(MD) and vacuum heat drying(VHD) were adopted to dry M. charantia, and then the effects of six drying methods on texture quality and related physicochemical indices during processing were studied. 【Result】For effects of different drying methods on nutritional ingredient and antioxidant, except for VFD, M. charantia processed by other methods had the same extract ratio of polysaccharide. M. charantia dried by HPD had the highest contents of polysaccharide of 29.22 mg·g~(-1) DW, while MD presented the lowest contents of 16.91 mg·g~(-1) DW. The contents of Vc, total phenolics, flavonoid, carotenoid and ORAC of different drying methods on M. charantia were reduced after processing. M. charantia dried by HPD had the highest contents of Vc(84.81 mg·100 g~(-1)), while MD contained the lowest(6.64 mg·100 g~(-1)). HAD had the highest contents of total phenolic and total flavonoid(32.04 mg GAE·g~(-1) and 7.44 mg CE·g~(-1), respectively), while VFD contained the lowest(14.14 mg GAE·g~(-1) and 0.36 mg CE·g~(-1), respectively). HPD had the highest contents of carotenoid(0.86 mg·g~(-1) DW), while SD contained the lowest(0.11 mg·g~(-1) DW). The highest ORAC was obtained from HPD, MD and VHD(226.44, 224.66 and 244.10 μmol TE·g~(-1), respectively), while the lowest was 113.23μmol TE·g~(-1), which observed in VFD. As for sense and physical properties, browning degree caused by thermal processing, but VFD presented the lowest browning degree. M. charantia dried by HPD had the highest contents of chlorophyll-a and chlorophyll-b, while SD contained the lowest. SD had the highest hardness, while VFD presented the lowest. As for microstructure, HAD, HPD and SD caused more shrinkage, and MD caused damage to structure, while VFD and VHD effectively retained the myosin integrity of M. charantia slices. 【Conclusion】The results indicated that there were significant differences in nutrition and physical properties of M. charantia among different drying methods. The best nutrition and antioxidant activity were found in HPD and HAD. The bright color and good texture profile were found in VFD. M. charantia dried by SD and MD had the poor quality.
【Fund】： 广东省中国科学院全面战略合作专项资金竞争性分配项目(2013B091100011);; 广东省社会发展项目(2013B021800071)
【CateGory Index】： TS255.3
【CateGory Index】： TS255.3