高固形物浓度对大豆分离蛋白酸性蛋白酶酶解产物功能特性的影响

本文系统研究了提高固形物浓度对酸性蛋白酶酶法改性大豆分离蛋白分子量分布、氮溶解指数、分散稳定性、持水力、乳化性、起泡性和泡沫稳定性的影响。结果表明:大豆分离蛋白经过酸性蛋白酶控制酶解制备的改性大豆分离蛋白,其产物氮溶解指数、起泡性均有明显提高,分散稳定性略有提高;但持水力、乳化性、泡沫稳定性有所降低。在相同水解度下,随着酶解体系中固形物浓度的提高,改性大豆分离蛋白的分散稳定性、持水力、乳化活性均呈上升趋势,酶解产物中分子量小于10 kDa的肽段以及氮溶解指数呈下降趋势。当水解度小于8%时,低浓度酶解产物起泡性高于高浓度酶解产物,而水解度超过8%时,高浓度酶解产物起泡性大体高于低浓度酶解产物。

Influence of High Solid Concentrations on the Functional Properties of Enzymatic Hydrolysates of Acid Protease from Soy Protein Isolates

The effects of solid concentration on molecular weight distribution, nitrogen solubility index, dispersion stability, water holding capacity, emulsifying property, foaming property and foam stability of soybean protein isolate were studied systematically in this paper. The results showed that the PR23-modifed soy protein isolate resulted in a higher NSI, foaming ability and dispersion stability, while lower water holding capacity, emulsifying activity and foam stability. High solid concentrations resulted in higher the dispersion stability, water holding capacity and emulsifying activity, while lower nitrogen solubility index and peptides concentration with molecular mass less than 10 kDa. When the degree of hydrolysis was less than 8%, the foaming ability of enzymatic hydrolysate of low concentration was higher than that of high concentration, while when the degree of hydrolysis was more than 8%, the foaming ability of enzymatic hydrolysate of high concentration was higher than that of low concentration.