改性前后大豆蛋白起泡性及相关性质的对比研究

摘要

大豆蛋白具有一定的起泡性，可作为起泡介质和其他食品组分的补充物在食品中应用。大量有关食品蛋白的研究，旨在改变其低功能性、增加起泡性，从而使更多的蛋白应用到食品配方中。对比研究原料蛋白、碱性蛋白酶改性后蛋白的起泡性能、溶解性，同时从营养角度对样品氨基酸的组成进行研究分析。酶改性条件为底物浓度8%（w/v）、加酶量0.04%（w/v）、时间40 min、pH 8、温度50℃。在此条件下，改性蛋白的起泡能力（159.15%）与未改性蛋白（111.65%）相比得到改善，而对于泡沫稳定性，改性后蛋白并未得到改善。改性蛋白的溶解性与未改性原料相比提高了13.01%。所有样品的氨基酸组成基本满足FAO推荐的氨基酸含量要求。%Soy protein has a certain foaming capacity and can be used as a foaming agent, supplementation with other food ingredients in food applications. A large mumber of researches on food proteins are aimed at modifying low–functional proteins to enhance their foaming capacity so that more proteins can be apply to formulation.The foaming property ,solubility and amino acid composition of raw SPI and modified protein with alcalase were investigated. Suspensions of 8%(w/v)soy protein isolated(SPI)were treated with 0.04%(w/v)alcalase for 40 min at pH 8 and temperature of 50℃.The foaming capacities of the modified samples(159.15%)were improved compared with that of original protein(111.65%),and the foam stability was not improved. The solubility of the modified protein were improved by 13.01% compared with that of original protein. Samples of all the amino acids composition basically met the FAO recommended model of essential amino acids.