Study On Enzymatic Hydrolysis On Sesame Protein And Its Hydrolysates Effect Of The Harmful Materials

This article studied on the enzymatic hydrolysis of sesame protein which extracted from defatted sesame cake .The reseach mainly studied on the sesame protein extracting from the cake .selecting the hydrolysis protease and hydrolysis technological condition parameters.inproving the hydrolysates flavour ,and the hydrolysates antioxidative activity and blocking in N-nitiso and introsamine formation system . The experiment results as following:1 Taking the ratio of protein soluble from sesame as the criterion ,the sesame protein extrating optimum technology was :sesame flour/water ratio 1:20,pH 12.50 temperature 80C.Under this technology the protein solube ratio reach 79%.;and the protein deposition at the pH 3.42 to 3.97was optimum , the protein deposition ratio at 86%~97%.2 Taking degree of hydrolysis(DH) as criterion ,using pepsin typsin ,AS1.398,pancreatin and papain to select the optimum protease .The results indicated the hydrolysis ability was AS1.398> typsin > pancreatin > papain> pepsin, the AS1.398 had the good ability to hydrolyze the protein.The AS1.398 comes from microorgannism , and its is easy to get and it has a advantage of safety, unexpensive ,so it can be as an ideal protease to hydrolyzing sesame protein .3 Taking degree of hydrolysis(DH) as criterion .applying the four factors quadratic regression orthoganal rotation grouping equation experiment(l/2implement) to study the AS 1.398 hydrolyzed sesame protein.The results showed that the degress of hodrolysis (DH).significantly related with temperature (X1),substrate concentration (X2),enzyme/substracte (X3),hydrolyzing time (X4), which affected the DH when hydrolyzing the sesame cake protein.From the result we mormulated the regression equation as:Y=13.18-0.90X1-1.69X2+1.87X3+1.07X4-0.15X1X2+0.92X1X3-0.47X1X4-0.47X2X3+0.92X2X4X+0.15X3X4-0.12X12-1.94X22-0.65X32-1.05X42 .From the regress equation ,The optimum condition draw by computer as: X1=0, X2=0, X3=1.682, X4=1,this is to say ,the temperature at 45℃, protein substrate concentration at 5%, enzyme/substration at 9600u/g,hydrolyzing time at 122min. Under this technology ,the DH could reach 16.74%, acid soluble peptide 79.12%,average peptide chain length 6 oligo-peptide.4 Using P-CD and some flavor reagent improved the hydrolyzates .The experiment showed P-CD masked the bitter of hydrolyzates significantly and superior to the flavor reagent.When added the 1.5 - 2.5(w/v) P-CD,it was good at masking the bitter .5 The hydrolyzates had evident antioxidative effect for scavenging O2- ,the hydrolyzats which hydrolyzed 80min (DH15.23%) had the best scavenging ratio than others hydrolyzats.When the hydrolyzates concentration adding to 8mg/mL ,the scavenging ratio reached 85% or so ,and the scavenging ratio was strengthened as the dosage concentation increasing ,but it was weaker than vitamin C(IC5o is 1.44mg/mL) in scavenging O2-.6 The hydrolyzates had extremely effect on scavenging .OH ,and the ratio of scavenging could be strengthened as the dosage concentration increasing .At the low dose concentration ,the effect of scavenging .OH by different DH hydrolysates were no significant different ,but when the dose concentation incresaing at 0.6mg/mL,high DH hydrolysates scavening .OH better than the low DH hydrolysate .7 The hydrolyzates had the effect of inhibitting LPO,and the inhibitting effect was strengthened as the dosage concentration increasing .when the hydrolyzates concentration adding to 3 mg/mL .different DH hydralyzates inhibitting of PUFA LPO ratio reached 60% or so.8 The hydrolyzates had the effect of inhibitting the N-nitiso and blocking the nitrosamine formation ,and the inhibitting or bloching effect was strengthened as the dosage concentration increasing.When blocking in nitrosamine formation ,the hydrolyzates blocking in nitrosamine formation was better than the sesame protein ,and the hydrolyzates effect were strengthened as the DH...