Study Of Fermentation Process And Antioxidant Activity Based On Enzymatic Hydrolysates Of Buckwheat Oats And Pleurotus Eryngii

Non-dairy probiotic foods which have advantages of high dietary fiber,low cholesterol,low fat,have become the important trend of foods containing probiotic microorganisms.In this paper,it conducted systemic research of four aspects with buckwheat powder,oats powder and pleurotus eryngii powder as raw material.It studied on select amino acid formula and optimized the process of liquefaction and saccharification,then optimized the fermentation process with lactobacillus plantarum and lactobacillus casei strains and determined antioxidative activity.The results of this study were as follows:1.Buckwheat powder,oat powder and pleurotus eryngii powder were mixed in different proportions according to the principle of protein complementarity,then filtered the mixed powders of the highest nutritive value with the essential amino acid reference model and the score of ratio coefficient of amino acid(SRCAA).The best compounded proportion of materials results were: oat : pleurotus eryngii : buckwheat=2∶1∶11,and the SRCAA was 95.88,approaching to the amino acid reference model.2.On the basis of amino acid formula selection of mixed powders,the α-amylase and β-amylase were used to enzymatic hydrolysis.It studied the different enzymatic hydrolysis conditions,including enzyme dosage、hydrolysis time and hydrolysis temperature and detected reduceing suger content by single factor experiment and orthogonal design.The optimal results showed that α-amylase was 6 U/g,hydrolysis time was 40 min,hydrolysis temperature was 60 ℃,β-amylase was 1000 U/g,hydrolysis time was 2.5 h,hydrolysis temperature was 55 ℃.In this condition,the reducing suger content was 25.43%.3.Through single factor experiment and orthogonal design,It optimized the fermentation process of L.plantarum and L.casei with enzymatic hydrolysate of mixed powders.Based on single factor experiment and response surface method,explored the effects of inoculation quantity,inoculation proportion and fermatation time on viable count in fermentation medium.The best fermentation factors: inoculation quantity was 4%,inoculation proportion of L.plantarum and L.Casei were 1:1 and fermentation time was 10.8 h.In this conditions,viable count was 8.89 Lg CFU/m L.The nutrients of enzymatic hydrolysate of buckwheat,oat and pleurotus eryngii had changed after fermentation.The content of reduceing suger reduced,fat content was not changed,protein,polyphenols,flavonoids and polysaccharides havd a certain degree of improvement.4、Study on the antioxidant activity of enzymatic hydrolysate of buckwheat,oat and pleurotus eryngii before and after fermentation.The antioxidant capacity of the fermented enzymatic hydrolysate had been improved.Reducing power、DPPH· and superoxide anion capacities had small increased 0.51、6.85%、5.36%,respectively,·OH radical scavenging rate increased significantly by 43.19%,and total antioxidant capacity increased by 18.28 U/mL.The IC50 of the·OH、DPPH·and superoxide anion were 0.63 g/mL,48.17 mg/mL,1.49 g/mL,respectively.After fermentation,the total antioxidant capacity was 35.34 U/mL.In conclusion,the fermentation broth of enzymatic hydrolysate of buckwheat,oat and pleurotus eryngii will provide theories on the development of natural nutrition and healthy food,which combined the "natural,nutritional and healthy" advantages of cereal and edible mushrooms and beneficial function of lactic acid bacteria.