Effect of Processing Conditions on Physicochemical and Functional Properties of Soybean Residue and Soywhey

• Main Authors: Te-Hsein,Liu, 劉德賢
• Other Authors: Ming-Tsao,Chen
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/44423330952458304644

碩士 === 大葉大學 === 生物產業科技學系 === 97 === Okara and soywhey are the by-products obtained during the manufacturing of soy milk, soy bean curd and tofu pudding. Okara contains high moisture and is very perishable , thus, it is difficult to be vtilized. And soywhey is usually thrown away and pollute the environment. Therefore, if the soywhey can be utilized the pollution problem can should solved or reduced. This study was to investigate the effects of drying methods on the chemical and physical properties of the soy okara, and the utilization of soy whey. The soy okara and whey obtained from a local tofu company were dried by 37℃ hot air, 60℃ hot air or -20℃ freeze-drying , respectively, for 72hr. The chemical composition, isoflav -ones and dietary fiber (IDF and TDF) , and functional and physical properties were determined. The results showed that the isoflavones contents decreased after drying. The dietary fiber contents including IDF and TDF increased after drying . Emulsifying capacity, swelling, water holding capacity, thichening and water absorption ability were improved by drying. However, it was found that the freeze-drying was the highest efficient among the three drying methods, in reducing the water content in both okara and soywhey. In order to improve the utilization of okara and soy whey, the okara was added to manufacture yoghurt, and soy whey was fermented with lactic acid bacteria. It revealed that the overall acceptability was found higher in the yoghurt which was added with 10 % wet okara and 1% freeze-dried okara. And pH value and fat content decreased, while lactic acidity increased in the fermented soywhey.