转谷氨酰胺酶交联木瓜蛋白酶水解产物改善大豆分离蛋白乳化特性的研究

doi:10.13386/j.issn1002-0306.2013.06.057

转谷氨酰胺酶交联木瓜蛋白酶水解产物改善大豆分离蛋白乳化特性的研究

Study on effect of papin hydrolysis and TGase cross-linking on emulsifying properties of soy protein isolate

摘要

摘要: 为获得适宜添加到冰淇淋等冷冻食品中的大豆分离蛋白（SPI）,利用转谷氨酰胺酶交联木瓜蛋白酶酶解大豆分离蛋白产物来改善大豆蛋白的乳化特性。将样品经高压均质制成O/W型乳状液,研究不同水解程度的水解产物交联后对样品乳状液的粒度分布、表面积平均粒径、离心乳析率等的影响,同时研究了常温放置、低温放置（4℃）以及冷冻-解冻处理对酶改性蛋白乳状液聚集、聚结稳定性的影响。结果表明,SPI和中低度水解（DH2%¹0%）样品经转谷氨酰胺酶交联后乳化活性和乳化稳定性均显著提高,水解度10%样品交联后的乳化活性和乳化稳定性改善最显著。酶改性可以显著改善SPI新鲜乳状液的聚集稳定性,中度水解度（DH6%¹0%）SPI样品交联后聚集程度最低。冷藏不会明显损坏样品的聚集和聚结稳定性。冷冻-解冻处理使乳状液发生聚结现象,SPI乳状液的聚结程度最大,中度水解度（DH6%¹0%）样品交联后的聚结程度最小。因此,可将中度水解SPI交联样品用于对乳化特性要求较高的冰淇淋等冷冻食品中。

Abstract: The effect of papain hydrolysis and TGase cross-linking on emulsifying properties of soy protein isolate (SPI) was investigated. The effect of the cross-linking with samples on different degrees of hydrolysis on the particle size distribution, the mean diameter per particle surface area and the centrifugal creaming rate of the emulsions were analyzed. The effect of different store conditions, such as room temperature storage, cold storage and freeze storage, on the flocculation stability and coalescence stability of samples were also studied. The result showed that:in the range of degree of hydrolysis (DH 2%¹0%) , the emulsifying activity of papain hydrolyzed SPI improved with the increase of DH. TGase cross-linking improved the emulsifying stability effectively, especially the cross-linked hydrolyzed SPI with lower DH. The optimum emulsifying stability was obtained when cross-linked the hydrolyzed SPI in DH 10%. During room temperature, the flocculation stability could improve effectively by TGase cross-linking of papain hydrolyzed SPI (DH 6%¹0%) . Freeze-thaw process would decrease the coalescence stability of emulsion stabilized with SPI, and the emulsions stabilized with cross-linking of the hydrolyzed SPI (DH 6%¹0%) could improve the coalescence stability. Thus, these modified samples could be used in some frozen food.