大豆肽的分级膜分离研究

Fractional Ultrafiltration Separation of Soy Peptides

利用截留不同分子质量 (30 0 0 0u、1 0 0 0 0u和 5 0 0 0u)的切向流超滤膜将水解度为 1 4 .5 %的大豆肽按分子质量分为 4级 ,利用凝胶过滤色谱研究了大豆肽的分子质量分布及分级膜分离的效果 ,以及大豆肽膜分离时膜的通量和分离效能变化 ,并对不同分子质量段大豆肽的功能特性进行了研究 .结果表明 :分级膜分离方法对大豆肽能进行有效的分离 ;水解度为 1 4 .5 %的大豆肽中大多数的分子质量小于 5 0 0 0u ;不同分子质量大豆肽的溶解性、粘度、起泡性和乳化性不同 .采用全回流方式处理大豆肽粗品时 ,随着大豆肽浓度的提高 ,膜通量有所下降 。

The fractionation of soy peptides by ultrafiltration separation was studied. Soy peptides products(hydrolysis degree of 14.5%) can be separated into four components (>30 000 u?10 000～30 000 u?5,000～10 000 u and <5 000 u) in terms of its molecular weight using fractional ultrafiltration separation system. The molecular weight distribution of each group was determined by filtration chromatography. The result showed that fractional ultrafiltration separation can effectively separate soy peptides. The molecular weight distribution of soy peptides with hydrolysis degree of 14.5% mainly was below 5 000 u. The soy peptides with different molecular weight have different functional properties, such as solubility, viscosity, foaming property and emulsifying property. The membrane filtrated flux decreased but the efficiency and selectivity of membrane increased as the content of soy peptides increased with total reflux operation. It provided a feasible way to purify soy peptides by fractional ultrafiltration.