两种大豆分离蛋白的比较研究

本文以醇洗豆粕为原料制备大豆分离蛋白(SPI-A),并将之与传统的碱溶酸沉工艺制备的大豆分离蛋白(SPI-C)作比较,发现脱脂豆粕经醇洗之后所制备的大豆分离蛋白,其功能性质明显优于传统的大豆分离蛋白。凝胶性能研究表明样品SPI-A的凝胶强度是385.4g,明显高于样品CSPI(85.4g);样品SPI-A的乳化和起泡性能也有明显的改善;HPLC研究表明SPI-A和SPI-C两种样品几乎在同一时间出峰,但激光光散射分析表明样品SPI-A的流体动力学半径远比样品SPI-C的大,说明样品SPI-A形成的聚集体体积较大,结构较为疏松,而样品SPI-C所形成的聚集体体积较小且结构较为致密。

Characteristics Comparative Study on Two Extraction Types of Soy Protein Isolates

Defatted soy flakes were washed with aqueous alcohol and the resultant material was extracted with water to prepare soy protein isolate (SPI-A) with improved functional properties in comparing with the conventional soy protein isolate(SPI-C)extracted directly from the alkaline low-denatured soy flakes. Gelling property was determined by rheometer at the protein concentration of 12% (W/W) while the gel fracture force of SPI-A was 385.4g, substantially higher than that of SPI-C (85.4g). Emulsifying and foaming stability were also found to be improved through alcohol washing. High performance size exclusion chromatography showed that when SPI-A and SPI-C were both eluted around the same time, the laser light scattering analysis indicated that SPI-A solution contains particles with larger hydrodynamic radius than SPI-C, suggesting that SPI-A forms larger protein aggregates with more flexible structure whereas SPI-C forms smaller and more compacted aggregates.