酱油的主要成分冷冻分配规律

Studies on the Distribution of Components in Soy Sauce During Freezing

对酱油进行冷冻分离试验并绘出相应冻结曲线,确定初温25℃、质量为1 000 g,可溶性固形物含量为35%的酱油,其冰点为-20.3℃,完全冻结温度为-30℃,完全冻结时间为4.17 h。同时测定冷冻分离得到的冰相和液相中各主要成分。研究发现冷冻温度在-20.5^-28.5℃内,冷冻时间为48h时,各主要成分在两相中的浓度均随着冷冻温度降低而上升;而从两相中的质量分配规律可知,在液相中呈梯度下降,在冰相中则相反。其中对于酱油重要质量指标氨基酸态氮来说,液相中其浓度由初始的8.8 mg/mL增加到-28.5℃下11.68 mg/mL,且其表观分配系数K值相对其他组分较低,有利于液相中得到浓缩。进一步研究发现,组成氨基酸态氮的各氨基酸中G lu,Leu,Asp更容易在液相中得到浓缩。

The soy sauce was separated by freezing. The freezing point of 35% soluble solid soy sauce was -20.3℃ ,and it was frozen at -30℃ for 5ho At the same time the physical and chemical indicators of the components was measured in two - phase soy sauce. The result showed that the concentration of some components have increased in two -phase as the temperature decreased. The mass components in ice phase increased as the temperature decreased but the mass distribution in liquid was on the contrary. The concentration of amino acid nitrogen which was the most important indicator increased from 0.88g/100mL to 1. 168g/100mL. The distribution coefficient showed that amino acid nitrogen was easier concentrated in the liquid phase with the temperature decreased. The further study showed that amino nitrogen component Glutamic acid, Leucine, Aspartic acid were all more easily concentrated in liquid phase.