Tracking the variation of soy protein composition during yuba preparation and cooking process

This study focused on the effects of different protein-lipid ratio on the yield, lipid seepage and cooking quality of soymilk-based yuba. Results showed centrifugation could be a good way to prepare soymilk with different protein-lipid ratio, without altering the protein composition of soymilk. Yuba yield could be improved by increasing protein-lipid ratio of soymilk. Meanwhile, insoluble aggregates were more easily formed in high-protein soymilk, resulting in limited protein utilization for yuba preparation. With the increase of protein-lipid ratio (from 2.04 to 4.69) in soymilk, the tensile strength of yuba (the 2nd film) increased (from 10.81 to 16.58 g/mm2), the lipid seepage rate decreased (from 72.26% to 0%), and the cooking loss rate decreased (from 44.30% to 35.53%). β subunit and B polypetides were more inclined to participate in yuba and more difficult to be removed from yuba during cooking process, thus contributed greatly to yuba texture. The present study demonstrated that high protein-lipid ratio in soymilk could enhance the strength and improve the yield of yuba due to the more participation of β subunit and B polypeptides, which provide practical and fundamental information for obtaining yuba with desirable properties.