Functional Porperties Of Pea Proteins Modified By Enzyme

The pea proteins, a byproduct of starch processing, were limited hydrolyzed withdifferent proteases. Functional properties were chosen as the evaluation indexes, theenzymatic hydrolysis conditions of pea proteins were optimized by Response SurfaceMethodology (RSM) based on single factor experiments. The functional properties,molecular weight distribution and application in meat emulsion of pea proteinsmodified by Enzyme were explored.Firstly, emulsion of pea proteins modified by Alcalase and Neutrase wereinvestigated. The modification effect of Neutrase was better than Alcalase. Theoptimal enzymatic hydrolysis conditions for Neutrase were: ratio of enzyme andsubstrate0.13%(w/w), time29.0min, temperature52.8℃, pH8.0, and substrateconcentration8%(w/v). Under these conditions, the emulsification activity index ofmodified pea proteins was35.78m2/g, and the emulsion stability was46.10min, andthey were27.48m2/g and35.65min of unmodified pea proteins, respectively.Modification could improve the emulsion of pea proteins significantly.Secondly, foaming properties of pea proteins modified by Alcalase, Neutrase andFlavourzyme were investigated respectively. The modification effect of Alcalase wasthe best, and the optimum hydrolysis conditions for Alcalase were: enzyme/substrate0.16%, time32.5min, temperature55.4℃, pH8.0, substrate concentration8%. Thefoaming ability and the foam stability of pea proteins before modification were185.5%and15.65%, and those of modified pea proteins were315.69%and63.47%.Foaming properties of pea proteins were significantly improved by enzymaticmodification.The results of the functional properties and molecular weight distribution showedthat in deferent pH and salt concentration, the Nitrogen Solubility Index (NSI),emulsion and foaming properties of modified pea proteins were all better than thoseof unmodified pea proteins. The structure of pea proteins was changed after enzymolysis. The proportion of molecular weight below2000in the Alcalasehydrolysates was risen from9.37%to20.92%, and the proportion of molecularweight from2000to10000in the hydrolysates prepared by Neutrase was risen from12.85%to32.18%.The results of the application of the hydrolysats in meat products showed thatadding modified peas proteins could reduce the cooking loss of worm, and the textureproperties of the worms were improved. Modified pea proteins were expected toreplace soy proteins applied in the meat processing.