Effects of Soy Protein Isolate and Its Different Enzymatic Hydrolysates on Emulsion Stability of Non-dairy Creamer

Abstract

In order to study the effects of soy protein isolate and its different enzymatic hydrolysates on the emulsion stability of the non-dairy creamer,the electrophoretic subunit composition of protein,molecular weight distribution,emulsifying activity and emulsion stability,the microstructure of non-dairy cream powder and emulsion,average particle size,ζ-potentials and coffee stability were measured in this paper.The results showed that the pepsin hydrolysate retained more 7S and basic subunits,and the product had the best emulsifying properties,which increased by 22.7% and 14.1%,respectively,compared with the emulsification activity and emulsion stability of SPI. The papain hydrolysate was mainly a small part of basic subunits and a large number of small peptides. Although the emulsification activity was increased compared with SPI,the emulsion stability was reduced by 17.6%. The SEM pattern of the non-dairy creamer and the CLSM pattern of the emulsion after the dissolution of the non-dairy creamer confirmed that the product prepared by the SPI pepsin hydrolysate had the best emulsification effect,and the coffee stability results showed that both hydrolysates could be used for coffee companion. The composition of the three proteins,the emulsifying properties,the microstructural result of the non-dairy creamer and the emulsion after the reconstitution of the non-dairy creamer showed that there were too many small peptides in the enzymatic hydrolyzate,and it was not conducive to the emulsion stability. There were more 7S protein and basic subunits will help to form a more stable emulsion.