Osullivan M M, Kelly A L, Fox P F
Department of Food Science, Food Technology and Nutrition, University College, Cork, Ireland.
J Dairy Sci. 2002 Jan;85(1):1-7. doi: 10.3168/jds.s0022-0302(02)74045-9.
Treatment of milk with transglutaminase (TGase) affects its heat stability, but the manner in which it does so depends on whether or not the milk had been preheated before incubation and on the temperature of preheating. In raw milk, it appears that cross-link formation between the individual caseins is responsible for preventing the dissociation of kappa-casein from the micelles at pH values in the region of minimum stability. In milks preheated before incubation with TGase, denaturation of whey protein may have allowed the formation of cross-links by TGase between denatured whey proteins and the individual caseins which, in combination with cross-linking of the caseins, contributed to greatly improved heat stability at pH > 6.5. It appears from the results of this study that TGase has potential commercial applications as a food-grade additive capable of improving the heat stability of milk.
用转谷氨酰胺酶（TGase）处理牛奶会影响其热稳定性，但其作用方式取决于牛奶在孵育前是否已预热以及预热温度。在生牛奶中，似乎单个酪蛋白之间形成的交联负责在最低稳定性区域的pH值下防止κ-酪蛋白从胶粒中解离。在用TGase孵育前预热的牛奶中，乳清蛋白的变性可能使TGase在变性乳清蛋白和单个酪蛋白之间形成交联，这与酪蛋白的交联相结合，有助于在pH>6.5时大大提高热稳定性。从本研究结果来看，TGase作为一种能够提高牛奶热稳定性的食品级添加剂具有潜在的商业应用价值。
