大豆分离蛋白流变学特性的研究

The Research on the Rheological Properties of Soybean Protein Isolate

大豆分离蛋白是以低变性脱脂大豆粉或浓缩大豆蛋白为原料，经碱、酸等一系列处理后得到的组分较均一、机能特性较强的蛋白质。大豆分离蛋白的等电点在ｐＨ４．２～５．６范围内。在该范围内大豆分离蛋白的溶解性、粘度、起泡性及泡沫稳定性、乳化性及持水性最弱；在该范围的两侧，随酸度或碱度增加，这些特性逐渐增强。大豆分离蛋白的粘度随浓度增加而增大，数学模型为ｙ＝１．１０３ｅ^（０．６０２８ｘ）＋１．０６，表现为非牛顿假塑性流体。

n the rangu of pH 4. 2 to 5.6 where soybean protein isolate(SPI) has the iaselectric point SPI expresses weaker solubility, viscosity, foam-yielding capacity. At the temperature over 50 ℃ SPI denaturates rapidely, its solubility and viscosity are decreased and foam-yielding capacity is increased. The solubility and viscosity are decreased when inorganic salts are added into SPI solution. The result shows that the viscosity of SPI increases with the concentration of SPI solution increases, the formula :Y=1. 1033e￣(0.6028X)+1. 06 indicating the SPI solution is a non-Newtonian poudoplastic fluid.