TGase交联对alcalase水解大豆分离蛋白起泡性的影响

摘要

In order to improve the foaming properties of soy protein isolate （SPI）, transglutaminase （TGase） cross-linking was employed for the large （Mw 〉 10 ku） and small molecular peptides （Mw 〈 5 ku） that hydrolyzed from SPI with alcalase. The results demonstrated that： TGase cross-linking could effectively improve the foaming property of SPI, especially improve the foam stability effectively; for the large molecular peptide （Mw 〉 10 ku）, the optimum foam stability （88.5%） was obtained with 15 U/g substrate of enzyme and 4 h of cross-linking time; as for the mixture of large molecular peptide （Mw 〉 10 ku） and small molecular peptide （Mw 〉 5 ku）, the optimum foam stability （60. 3% ） could be obtained by 50 U/g substrate of enzyme, 4 h small molecular peptide; the molecular weight of the cross-linking of cross-linking time with 1：1 molar ratio of large and products from large molecular peptide （Mw 〉 10 ku） was higher than that from the mixture of large（MW 〉 10 ku） and small （MW 〈 5 ku） molecular peptide. The research may provide certain theoretical basis for improving the foaming property of SPI by enzymatic method.%为了提高大豆分离蛋白（SPI）的起泡性，对SPI经alcalase有限水解产物中不同分子大小的肽段采用谷氨酰胺转移酶TGase进行交联。结果表明：TGase交联可有效提高SPI的起泡性，特别是显著地提高了其泡沫稳定性；MW〉10ku的大分子肽当加酶量为15U／g底物且交联4h时得到最佳的泡沫稳定性为88．5％；MW〉10ku和MW〈5ku的大分子和小分子肽混合物当加酶量为50U／g（底物），交联时间为4h、大分子与小分子肽摩尔比为1：1时得到的最佳泡沫稳定性为60．3％；MW〉10ku的大分子肽交联产物的分子质量显著高于MW〉10ku的大分子肽和MW〈5ku的小分子肽（摩尔比1：1）交联产物的分子质量。