Enzymatic Hydrolysis Of Goat's Whey Protein And Development Of Goat's Whey Beverage

The paper was aimed at studying the optimum techniques ofenzymatic hydrolysis of Goat's whey protein, stability of hydrolysate and thedevelopment of Goat's whey beverage. The purpose of this study is to determinethe optimum proteases combination, the suitable hydrolysis parameters, the bestdebittering conditions and the most appropriate formulas of flavor and technologyprocess of the beverage. In addition, the pH stability and thermal stability ofGoat's whey hydrolysate were also discussed in detail.Alcalase, Protamex and Flavourzyme were applied to Goat's whey protein forhydrolysis at their favorite conditions separately with DH% and value of bitternessas guides. The results indicate that: each protease at its optimum conditions tohydrolysis Goat's whey protein, DH% is Protamex 34.78%, the largest one,secondly is Alcalase, DH% is 29.23%, the last one is Flavourzyme, DH% is26.05%; thereinto, the hydrolysate which by Flavourzyme, its flavor is the bestone.Abased on the single protease hydrolysis, the optimum conditions ofenzymatic hydrolysis were studied with the degree of hydrolysis and bitterness, tostudy on hydrolysis of Goat's whey protein by double proteases. The experimentalresults show that: the step hydrolysis parameters of Alcalase and Flavourzyme,DH% can go up to 35.83%; the step hydrolysis parameters of Protamex andAlcalase, DH% can reach 35.53%; the step hydrolysis parameters of Flavourzymeand Alcalase, DH% is 32.81%, and this hydrolysate has good test. Therefore,choose the step hydrolysis parameters of Flavourzyme and Alcalase as the motherliquid of producing Goat's whey beverage.The dissertation research on the pH stability and thermal stability of Goat'swhey is studied too. As the result of the test shows, enzymatic hydrolysis canreach the pH stability and thermal stability of Goat's whey at different extent.Goat's whey hydrolysate by proteases tasted bitter. The bitterness ofhydrolysate can reduce byβ-cyclodextrin. 0.6% ofβ-cyclodextrin was used as thescreening agent to effectively embed bitterness. The hydrolysate which had been debittered was prepared into Goat's wheybeverage using single factor and orthogonal design. The most appropriate flavorformula was: sucrose 6%, mixed acid (Citrate acid: Malic acid=1:1) 0.30%, honey1.33%; when the materials were added into the beverage, it tasted very good andlook very uniform without deposit. The proper sterilizing conditions were 85℃and 30min. The storage stability of Goat's whey beverage isstrong.