以大豆分离蛋白(soy protein isolate,SPI)和乳糖(lactose)为原料,研究了固相混合体系经不同微波处理时间后分子质量、自由氨基及流变性能的变化。结果表明:随着微波时间的延长,SPI分子质量分布向高分子质量偏移,自由氨基含量显著降低。SPI经微波糖基化处理120 s后,溶液的流变特性发生改变,与未处理SPI相比呈现出更大的弹性。动态黏弹性分析表明,改性后样品溶液储能模量随温度变化不明显,而原样SPI溶液储能模量在降温阶段明显增大,可为具有热加工稳定性的新型大豆分离蛋白的研发提供一种新途径。

Soybean protein isolate(SPI) and lactose were used as raw materials,and the changes of molecular weight distribution,content of free amino group and rheological properties after microwave heating in different time in solid state were explored.The results showed that the molecular weight distribution of SPI shifted to the higher bands,the content of free amino group significantly decreased.Compared with untreated SPI,the rheological properties of SPI treated by microwave glycosylation for 120 s significantly changed.The microwave treated samples showed greater flexibility.Dynamic viscoelastic analysis showed that the storage energy capacity of modified sample was not obvious with temperature change,and storage capacity of the untreated SPI increased obviously at cooling stage.