Screening Of Cactus Wine Yeast And Optimization Of Fermentation Process

The "Mibangta" edible cactus has medicinal and health-care functions,it as a raw material to produce cactus wine,which not only retained its original value,but also increased the yeast fermentation metabolite.In this study,the viscosity of cactus pulp was reduced and the finest cactus wine brewing Yeast was screened,at the same time,the fermentation conditions of cactus wine were optimizedand and the cactus wine was evaluated The research results are as follows:1.The cactus clear juice was prepared by enzymatic hydrolysis with pectinase,cellulase,a-amylase,acid protease and glucoamylase,and the water was determined.The multi-factor analysis of variance showed that the difference of cactus juice yield was extremely significant.After the compounding ratio of the complex enzyme was determined,multivariate analysis of variance showed that the five enzymes were extremely significant for the difference in soluble solids in cactus juice,and finally the ratio of the juice to the water was 1:4,the complex enzyme(cellulase:pectinase:a-amylase:Acid protease:glucoamylase was 3:4:1:1:1)added 0.70%,the two-stage enzymatic hydrolysis was used,the cactus juice soluble solids reached 2.20%at 50? for 3 h and 60? for 2 h.2.The traditional separation method was used,61 strains were isolated from cactus fresh juice and natural fermentation broth.Four strains of Saccharomyces cerevisiae and 8 strains of Non-Saccharomyces cerevisiae were screened by preliminary identification and tolerance test in WL medium and lysine medium.The bacteria were inoculated in cactus juice at a ratio of 5.00%of these 12 strains for fermentation,compared with the commercial Saccharomyces cerevisiae FTH,the physicochemical indexes,volatile components and sensory evaluations of the cactus wine after fermentation were determined,and the excellent bacteria ZRF5 and non-Saccharomyces cerevisiae Z5 were obtained.It was identified by 26S rDNA technology,ZRF5 was Saccharomyces cerevisiae and Z5 was Pichia kluyveri.3.Synchronous and asynchronous inoculation fermentation experiments with ZRF5 and Z5 yeast.By comparing physical and chemical indicators,volatile components and sensory evaluation,which was found that Z5 and ZRF5 yeast interval 48h sequential inoculation fermentation method was better.The optimal fermentation process was deternined by response surface-principal component analysis method:the yeast inoculation ratio of 1:1,the yeast inoculum of 5.40%,the initial sugar content of 23.00%,the fermentation temperature of 20?,and the fermentation of 10d.The degree of 11.51%,the flavonoid content of 5.35 mg/L,the total phenol of 55.86 mg/L,the residual sugar of 2.84 g/L,and the total acid of 4.76 g/L.4.Compared with NY/T 1508-2017 standard.The cactus alcohol,residual sugar and total acid content of the cactus produced in the experiment were in line with the standard.The cactus body was light yellow,clear and transparent,containing 8 kinds of amino acids essential for the human body.A total of 48 volatile substances were detected in cactus wine,among which Phenylethyl Alcohol,Benzenemethanol-alpha-methyl,Ethyl octanoate,Ethyl caprate,2,3-Butanediol,2-Pentenal,3-Hydroxy-2-batanonc,etc.these substances gave a unique style to the cactus wine.In vitro antioxidant experiments showed that it had a certain antioxidant capacity.The experiment provides a theoretical basis for the actual production by screening the special yeast suitable for the fermentation of cactus wine for mixed fermentation.