Oxidation reactions in model systems simulating the processing of soybeans into soymilk: role of lipase and lipoxygenase in volatile flavors formation

In recent decades, the process of lipase (LIP) activation hydrolysis and lipoxygenase (LOX) oxidation for energy supply during soybean germination has been well understood, but the formation mechanism of volatile flavor substances in soymilk grinding has not been understood in detail. Different model systems were prepared using protein, LOX, LIP, and triacylglycerol (TAG) derived from soybeans to study the reaction process of soymilk flavor. The study revealed that the simultaneous existence of LOX, LIP, and TAG was a necessary condition for flavor formation, and the type and amount of volatile flavor substances were related to the composition of the lipid substrates. Compared with soymilk, the model system with LOX and LIP had a high degree of similarity in the composition of volatile flavors, but there were differences in quantity. This indicates that the flavor formation of soymilk is also positively influenced by other ingredients in soymilk.