Effects of small molecular compounds in soymilk on the protein coagulation process: Ca2 + as coagulant
Effects of small molecular compounds in soymilk on the protein coagulation process: Ca2 + as coagulant
复制标题
DOI：
10.1016/j.foodres.2015.04.019
复制
发表时间：
2015-11
影响因子：
8.1
通讯作者：
Ruican Wang;Laichao Xie;Shuntang Guo
中科院分区：
文献类型：
--
作者：
Ruican Wang;Laichao Xie;Shuntang Guo
为明确豆乳中小分子物质对豆乳蛋白质凝固过程的影响，对66个大豆品种的豆乳蛋白质凝固特性进行了统计分析。蛋白质沉淀量（mg/mL）与氯化钙浓度（mM）的函数关系曲线符合Logistic方程（y=a/（1 +B* exp（−kx）。该曲线包括两个缓慢上升阶段（x= 0 ~（lnb-1.317）/k和x =（lnb+1.317）/k）和一个急剧上升阶段（x=（lnb-1.317）/k~（lnb+ 1.317）/k）。参数a因大豆品种而异，与豆乳中可溶性蛋白含量（最大沉淀量）呈正相关。参数“B”和“k”与豆浆中可溶性蛋白质和磷的含量相关，反映了蛋白质与凝固剂之间相互作用的几率。当使用超滤模块（截留分子量为10 kDa）去除或减少豆奶中的小分子时，曲线的起点和终点向前移动，蛋白质聚集更快，更容易发生。进一步证实了多酸离子等小分子可以降低蛋白质分子与Ca 2+直接相互作用的几率，从而使蛋白质对Ca 2+的敏感性降低。因此，蛋白质凝固反应应该是在以植酸盐等多酸离子为主的小分子与Ca 2+相互作用形成不电离物质后发生的。然后蛋白质分子聚集、生长并形成网络。
In order to clarify the roles played by small molecular compounds in soymilk on its coagulation process, characteristics of protein coagulation for soymilk from 66 soybean varieties were statistically analyzed. The curve, namely the function between protein precipitation amount (mg/mL) and calcium chloride concentration (mM), fitted well with Logistic equation, (y=a/(1 +b* exp(−kx))). The curve included two slowly increasing stages, which indicated the initial and later periods, (x= 0 ~ (lnb− 1.317)/kandx= (lnb+ 1.317)/k∼ ∝) and a sharply increasing stage (x= (lnb− 1.317)/k~ (lnb+ 1.317)/k). Parameter “a” differed among soybean varieties and it was positively correlated with soluble protein content in soymilk, referring to the maximum precipitation amount. Parameters “b” and “k” were correlated with the contents of soluble protein and phosphorus in soymilk, reflecting the odds of interactions between protein and the coagulant. When small molecules were removed or reduced from soymilk using an ultrafiltration module (cut-off 10 kDa), the start and end point of the curve moved forward and aggregation of protein was quicker and more easily happened. It was further verified that small molecules like polyacid ions could lower the odds of direct interactions between protein molecules and Ca2 +, so that the protein became less sensitive to Ca2 +. Therefore, the protein coagulation reaction should occur after the small molecules, mainly phytate and other polyacid ions, interacted with Ca2 +and formed unionizable substances. Then the protein molecules aggregated, grew and form a network.