High Sulphur-content Peptide Zein Hydrolysate Preparation And The Exploration Of Its Application

Combined with the existing zein hydrolysate modification technique to researchnew modification methods, first preprocessing in order to increase the subsequenthydrolysis of protein: adopt the role of high-speed shearing force will be commerciallyavailable flake zein pieces is100~120mesh powder; Using novozymes alkalineprotease and papain in pretreatment on the basis of using distribution of two-stagehydrolysis method, to reduce the molecular weight as the main means, to improveprotein hydrolysis rate and solubility in water: the speed of dispersion feeding material2~5g/min, the first level hydrolysis: pH9.5, material liquid ratio1:50, temperature58℃,alkaline protease enzyme dosage1%, temperature and enzymolysis time2.0h, at lastprotein hydrolysis rate81%; Secondary enzyme hydrolysis: papain enzyme dosage0.5%of58℃, temperature, digestion time2.5h, pH7, final protein hydrolysis rate canreach92.5%, protein molecular weight reduced to1500Da, the water-soluble of thezein were markedly enhanced.According to the principle of thiol exchange and rearrangement, install thesulfhydryl resin column and dynamic adsorption elution method to extract containingsulphur from protein hydrolysate and disulfide bond short peptide: sulfhydryl resincolumn Φ2.5x75cm, the actual column volume of about368ml, protein hydrolysatediluted10times after the column, the column pH9.5, flow rate of100ml/h (0.27BV/h),they can exchange the hydrolysis of diluent maximum volume for350ml;Wash resincolumn with5BVdeionized water, and blended with1.5BV hydrochloric acid andvitamin C eluent (HCl:2mol/L, Vc:2mg/mL) in200mL/h elution velocity. Afterultrafiltration and lyophilization income producing is the thiol peptide powder. Thiolpeptide with Zn2+the best chelating pH6; Zn2+and thiol peptide chelate ratio is about1:2. Chelate reaction time is about100min. The chelate is the imitation ofmetallothionein. In imitation of metallothionein crystal morphology, ir, melting point,differential thermal analysis, through the analysis on the characterization, finaljudgement chelating effect.