酸法去酰胺提高大豆分离蛋白持水性的研究

Study on Improving the Water Absorption Capacity of Soybean Protein Isolate by Acidic Deamination

为了提高大豆分离蛋白(SPI)的持水性,采用HCl对SPI进行去酰胺改性。采用响应面分析法,以持水性为响应值,研究了HCl浓度、反应温度、反应时间对SPI持水性的影响。并对去酰胺改性前后的蛋白样品进行疏水性和电镜扫描(SEM)的测定与分析,结果表明:HCl对SPI能够发挥去酰胺作用,其酸法提高SPI持水性优化的工艺条件为HCl浓度0.21 mol/L、反应温度66℃、反应时间3 h。该条件下生产的SPI样品与未改性的SPI样品相比,持水性由5.60 mL/g提高到7.82 mL/g,提高了39.6%,其脱酰胺程度为24.5%。

In order to enhance the water absorption capacity of SPI, Soybean protein isolate （SPI） was modified through hydrochloric acid deamination. Response surface methodology was used to optimize the factors such as the density of hydrochloric acid, temperature and time. The water absorption capacity were determined and analyzed in various conditions. Hydrophobicity determination and scanning electron microscope （SEM） analysis were conducted to confirm the deaminated SPI by hydrochloric acid. The results showed that the optimum conditions to achieve the maximum water absorption capacity were as follows： the density of hydrochloric acid 0.21 mol/L, temperature 66℃ , time 3 h. Under such conditions, the water absorption capacity was improved 39.6% from 5.60mL/g to 7.82 mL/g. The deamination rate was 24.5 %.