Research On Preparation Of Whey Antioxidant Peptides And Industrial Separation And Purification Technology

Whey is product of producing cheese and casein,whey is very nutrient contain alots of functionalitycomponent.Active prptides from whey protein have the actively of antioxidation actinety and the angiotensinⅠconverting enzyme（ACE）inhibitory activety,so on.This thesis mainly study whey protein on alcalase enzymeshydrolysis purification.moreover,the purity of whey antioxidant peptide was improved in industry process.Through the test to determine the whey antioxidant peptide industrialization technology parameters. Theeconomical and reliable methods,the efficient and practical technologies were utilized for high quality and highpurity whey antioxidant peptide preparation.Three research contents were included in this study:1.The optimization of complex formulation of high-yield whey antioxidant peptides by enzymatichydrolysis.Whey protein hydrolysis can produce with antioxidant activity of peptide material, but its antioxidantactivity was related to content, the concentration.Whey proteins could be hydrolyzed with alcalase, neutrase andtrypsin. The optimum parameters of whey antioxidant peptide including hydrolyzing degree and TBARS valuewith different enzymes, at different hydrolytic times, temperatures, pH,enzyme addition and substrateconcentration were certained in the paper. The results were that the hydrolysates of whey proteins hadantioxidation. The optimal blends with conditions were that whey proteins could be hydrolyzed with alcalase for5h, hydrolytic temperature was65℃, pH was8.5and also with trypsin for1h,hydrolytic temperature was45℃,pH8.0. Whey peptide had strong antioxidant capacity when hydrolyzing degree was32.28%.2. The technical parameters of whey antioxidant peptide separation by macroporous resin were studied.Whey hydrolysates is a mixture, in order to improve the whey antioxidant peptide purity, and improve itsantioxidant activity, static adsorption test was applied for resin screening based on the results of adsorption apacityand desorption, HDP400A was chosen from XAD-7HP, XAD-761, HDP400A, HDP400as the optimization resinfor whey antioxidant peptide purification. The experiments were carried out to investigate the elution rate,elutiontime, sample size, elution concentration, The optimum process parameters were saturated extent of adsorption0.08g/mL, elution rate5mL/min, elution time30min, sample size3mL,concentration of ethanol40%,amount ofeluent280mL.3.Determination the pilot scale experiment parameters of whey antioxidant peptide separation by SMB. Inorder to realize the industrialization, according to the paramters of macroporous resin separation from wheyantioxidant peptide and the selected conditions range, design industrialization technology parameters and pilot.The results of single column preparative chromatography validation test, the industrialization technical parameterswere designed and carried out with pilot scale experiment, the optimum SMB separation conditions were:flow rate14.0mL/min，water1rate32.0mL/min，ethanol desorption rate28.0mL/min，water2rate30.0mL/min andswitching time780s.The purity was93.0%and yield coefficient was92.0%.Whey antioxidant peptide molecularweight was the scope for400~700Da, and molecular weight for467Da of whey peptide up to70%above.The research proves that the key of whey protein antioxidation peptide yield is selection of complex enzymein the process of whey protein hydrolysis. The resin of HDP400A is selected for SMB of whey proteinantioxidation peptide. The key of the separation is elution velocity and sample size; purity of whey proteinantioxidation prpited is93.0%, yield is92.0%using the SMB.This isolation method is the better than others...