冻融循环对酶切糖基化大豆蛋白稳定性的影响

Influence of Cycle of Freezing and Thawing on Stability of Glycosylated Soy Protein by Enzyme Digestion

为研究酶切糖基化大豆蛋白的实际应用效果,采用限制性酶切大豆分离蛋白(SPI)-葡聚糖糖基化产物,以表面吸附量、乳析指数、平均粒度、显微结构为评价指标,比较了分别由SPI、SPI与葡聚糖的糖基化产物(SPID)、酶切糖基化大豆蛋白产物作为乳化剂的乳化体系的冻融稳定性。结果表明,经3次冻融循环后,酶切糖基化大豆蛋白产物乳化体系仍保持较好的稳定性,显著高于SPI、SPI-D对照组。限制性酶切糖基化大豆蛋白可用于改善食品乳化体系的冻融稳定性,为生产冷冻产品专用大豆蛋白提供理论依据。

A novel emulsifier was prepared by conjugating soy protein isolate and dextran under wet-heated Maillard reaction followed by trypsin hydrolysis, The freeze-thaw stability of soy protein isolate, soy protein isolate-dextran conjugates and hydrolysates of soy protein isolate-dextran conjugates were investigated. In this study, we have used fraction of protein adsorption, droplet size, creaming index and microstructure measurements to treat emulsions. The results showed that hydrolysates of soy protein isolate-dextran conjugates were capable of forming a fine emulsion which remained stable after three freeze-thaw cycles and had a much higher fraction of protein adsorption compared with soy protein isolate and soy protein isolate-dextran conjugates. Therefore, a combination of Maillard reaction and controlled enzymatic hydrolysis might be a promising way for the functionality, it will lead to the creation of food emulsions with improved stability to freezing and thawing. This method provides a theoretical basis for special soy protein which is more suitable for producing frozen foods.