大豆分离蛋白-花青素复合乳液稳定性研究

Stability of Anthocyanin-Soybean Protein Isolate Reconstituted Emulsion

以大豆分离蛋白和花青素为原料,制备热处理大豆分离蛋白-花青素复合乳液,研究添加花青素对复合乳液特性的影响规律。利用动态光散射从宏观角度评价花青素复合对复合乳液粒径大小以及分布上的影响,采用乳化稳定性、乳层析指数和ζ-电位分析,分别从不同的角度评价复合乳液的稳定性,结果表明:花青素复合后,复合乳液的粒径变小,乳层析指数显著降低,ζ-电位的绝对值增加,说明乳液液滴间的静电斥力大,不易发生聚集。蛋白与花青素的质量比为40的样品具有最低的CI值(41%)和最大的电位绝对值,说明在所有花青素复合的热处理SPI-花青素复合乳液中,其具有最好的乳液稳定性。氧化稳定性实验结果表明:随着花青素浓度的增加,乳液DPPH自由基和ABTS+·清除率先上升后略有下降,其中蛋白与花青素的质量比为40时,乳液抗氧化性最佳。因此在大豆分离蛋白中添加花青素可以有效提高复合乳液氧化稳定性。

The reconstituted emulsion prepared by soybean protein isolate and anthocyanin was studied.Dynamic light scattering(DLS)was used to evaluate the effect of anthocyanin on the size and distribution of reconstituted emulsion.And the stability of reconstituted emulsion was evaluated by emulsion stability and Zeta potential analysis.The results showed that the particle size of the reconstituted emulsion became smaller,the stability of emulsion was decreased significantly,and the absolute value ofζ-potential was increased.The sample of 40(mass ratio of SPI by heat treatment to anthocyanin)had the lowest CI value(41%)and the maximumζ-potential,which indicated that the reconstituted emulsion with certain amount of anthocyanins had the best stability.At the same time,the stability of emulsion oxidation showed that the scavenging ability of DPPH and ABTS was increased first and then decreased slightly with the increase of concentration of anthocyanin.And the reconstituted ratio of SPI by heat treatment to anthocyanin was 40,the antioxidant property of emulsion was the best.Therefore,the addition of anthocyanin could effectively improve the oxidation stability of the reconstituted emulsion.