大豆乳清蛋白的热促凝聚及其对分离蛋白功能性的影响

Thermal Aggregation of Soybean Whey Protein and Its Effect on the Functional Properties of Soy Proteins

分别在pH8．0和pH4．5对“碱提酸沉”法制备大豆分离蛋白过程中所得提取液进行热处理，研究了大豆乳清蛋白的热促凝聚效果及其对所制备分离蛋白功能性的影响。结果表明：加热处理可降低大豆乳清中乳清蛋白的含量，在pH8．0和pH4．5时提取液经70℃加热10min分别使25．7％和40％乳清蛋白转移到分离蛋白产品中。以普通分离蛋白为对照，对3种分离蛋白产品进行功能性分析，发现3种产品均在pH4．5～4．8的范围内溶解度最小，70℃加热10min所制备分离蛋白的持水性明显高于普通分离蛋白，但其持油性、起泡性、泡沫稳定性和乳化性均低于普通分离蛋白，而乳化稳定性无显著差异。

The reclamation of soybean whey protein （WSP） can bring economic benefits and reduce environmental pollution during soybean protein production. Extracts at pH 8.0 and pH4.5 were heated to observe the thermal aggregation of WSP and its effect on the functional properties of soy proteins. Results showed that heat treatment reduced the content of WSP in soybean whey, extracts at pH 8.0 and pH4.5 were heated by 70℃ with 10 minute diverted 25.7% and 40% WSP into soybean proteins Isolated （SP1） , respectively. Functional properties analysis of three kinds SPI indicated that they all had the minimum solubility during pH4.5-4.8. SPI preparing by heated by 70℃ with 10 minute bad higher water holding property than common SPI, but had lower oil holding property, foaming property and foaming stability than common SPI, and had no significant difference for emulsify stability.