The Peptide's Function Of Soybean Milk Fermentation By Lactobacillus Casei

With the further research on the function of probiotics and beans,the improvement of people's health awareness.The utilization of soybean plant protein to solve the deficiency of high quality protein has become the focus of competition and public concern in bean processing industry.Soy contains a variety of functional ingredients that are benefit to the human body and nutrients required for probiotic lactobacillus.Not only the fermented soybean milk improved the nutritional value,but also beneficial for human body to absorb protein,calcium,iron ions and vitamins.Lactobacillus casei as a typical probiotics,the probiotics and safety has been recognized internationally.Probiotics fermentation of soybean milk products has become a hot research topic.This paper study the fermentation characteristics of lactobacillus casei in soybean milk fermentation.At the same time,classified and quantified,the peptides produced in fermentation.Further tested the important biological functions of peptides?antioxidative and antihypertensive?and characterized by LC-MS/MS.This research uesd the activated strain Lactobacillus Z66,fermented the Soy milk,studied the fermentation characteristics of the strain.The results show that the pH dropped from 6.8 to3.6.During fermentation for 24 hours,the increase in height of 4log₁₀cfu/mL.The highest protein hydrolysis was?477.9±29.24?microns/mL,?-galactosidase showed the highest production activity18.19unit/mL.Through liquid chromatography analysis,compared with the oligosaccharide peak in unfermented samples,Lactobacillus Z66 showed significant utilization of sucrose and gossypol,The consumption rate was 95.04%and 53.47%,however,the utilization of trichosaccharide was less21.95%.Classified and quantified the peptides produced in fermentation.Further testedimportant biological functions of peptides.The results showed that the peptide content of 10KDa was?0.628±0.020?mg/mL,which showed the highest peptide content compared with 3KDa and5KDa,and the high antioxidant activity.The inhibitory activities of ABTS+and DPPH·were respectively?1831±20.29?TEAC mm and?50.74±0.27?%.On the contrary,it's no significant difference in ACE inhibitory activity.Through characterize by LC-MS/MS,identified the peptide sequence of 10KDa.At last,search for specific soy bioactive peptide data.The research showed18 kinds of peptides have antioxidant properties,16 kinds of peptides have ACE inhibition,17 biofunctional soy peptides showing both antioxidant and ACE-inhibitory activities.This study provides a scientific basis for the industrial production and popularization application to Lactobacillus casei fermented soybean milk products.At the same time,it also provides a new idea and method for the research and development toother multi-functional probiotic soy milk.