A1与A2 β-酪蛋白酸奶产品特性的比较

探究分别含有A1、A2两种β-酪蛋白牛乳制成的搅拌型和凝固型酸奶产品特性的区别。持水力结果表明，A1 β-酪蛋白酸奶（凝固型和搅拌型）的持水力大于69%，A2 β-酪蛋白酸奶（凝固型和搅拌型）的持水力大于65%。质构特性的结果显示，凝固型酸奶差距更为明显，A1 β-酪蛋白酸奶的硬度和稠度分别比A2 β-酪蛋白酸奶高41.4%和59.8%。此外，A1 β-酪蛋白酸奶黏性优于A2 β-酪蛋白酸奶。流变学特性与微观结构结果显示，A1 β-酪蛋白酸奶的滞后回路面积较A2 β-酪蛋白酸奶小14.6%，说明A2 β-酪蛋白制成的酸奶结构更易于被破坏，网状结构更为稀疏。本实验为A2 β-酪蛋白牛乳在酸奶制品的应用及实际生产提供一定理论支持。

Comparative Study on the Characteristics of A1 and A2 β-Casein Yogurt

The differences in characteristics between stirred and set yogurt produced from A1 or A2 β-casein milk were studied. The water-holding capacity of stirred and set yogurt produced from A1 β-casein milk was greater than 69%, and the water-holding capacity of stirred and set yogurt produced from A2 β-casein milk was greater than 65%. Textural analysis showed that the hardness and consistency of set yogurt produced from A1 β-casein milk were 41.4% and 59.8% higher than those of set yogurt produced from A2 β-casein, respectively. Compared with A2 β-casein yogurt, A1 β-casein yogurt had better viscosity. The results of rheology and microstructure showed that the hysteresis loop area of A1 β-casein yogurt was 14.6% smaller than that of A2 β-casein yogurt indicating that the former’s structure can be more easily damaged and its network structure is sparser. This study provides theoretical support for the application of A2 β-casein milk in yogurt.