The Study Of Microbial Fermentation Peanut Meal For Preparation Of Functional Peptides

In this thesis Aspergilleu oryzae and Aspergilleu niger which screened out fromAspergilleu oryzae, bacillus, Monilia tropicalis and Aspergilleu niger in vitroprobiotic property and peptide percent conversion were used to fermentate peanutmeal for preparation peanut peptides, and using response surface methodology tooptimize the fermentation conditions. Polypeptides by membrane separation methodfor separating different molecular weights, functional properties of differentmolecular weight peptide and its physical and chemical properties, of peanutpeptides used in food and used as additive has important significance.This thesis is divided into several parts as follows:The Aspergillus oryzae, Aspergillus niger, bacillus, Candida tropicalis, fourBacillus subtilis strains of bacteria were studied, including artificial gastric juice,artificial intestinal juice tolerance, bile tolerance and resistance to four kinds ofcharacteristics of salt, found that different growth curves of different, provide thebasis for the inoculation; different strains were different to reverse environmentaltolerance of different, but all have different levels of tolerance, and after24h tolerancehave been enhanced to a certain extent.Through the comparison of four species and two mixed antagonism test results,find out that the compatibility of several groups of strains combination of goodfermentation test, found the antagonistic effect of weak strain combination the peptideconversion rate is relatively high; the two test results are consistent inoculation. Bycompared peanut meal before the fermentation by polyacrylamide gel electrophoresis(SDS-PAGE) analysis, found before fermentation molecular weight in the rangebelow66KD, and the molecular weight of peanut meal after fermentationsignificantly reduced, no big molecular protein, with molecular weight below22KD. Screened Aspergillus oryzae and Aspergillus niger by controlling thefermentation process of strain ratio, fermentation temperature, fermentation time, brancontent and moisture content of six factors, at the same time, pick one of effect ofratio, strain fermentation temperature, high bran content, water content of responsesurface optimization, get good optimization effect.The physicochemical properties of peanut meal functional oligopeptides werestudied, fermentation of peanut meal with oil absorption, foaming and foam stability,emulsification and emulsion stability is very good, and has a solubility andhygroscopicity worse. Short peptide and different molecular weight of itsphysicochemical properties are difference.The peanut meal functional peptide of hydroxyl radical scavenging activity,DPPH radical, superoxide anion free radical, iron, molybdenum also force, ironchelating ability, copper chelating ability and linoleic acid antioxidant capacity, foundthey have a large difference in the antioxidant activity of different molecular weightpolypeptide.