Study And Preparation Of Papaya Jiaosu

Jiaosu is a kind of new product which come to China in recent years.Using papaya and granulated sugar as raw materials,papaya jiaosu was prepared under field condition.The microbial community of the papaya jiaosu was explored through metagenomic analysis.At the same time,the isolation and identification of cultures in papaya jiaosu were studied and the strains were applied in the fermentation of papaya ferment.Several indexes were monitored in fermentation process which including field condition and inoculated condition.Antioxidant capacity of papaya jiaosu was also analysed in vitro condition.Several indexes were compared between papaya jiaosu and orther jiaosu products.Using papaya jiaosu as material a kind of papaya jiaosu drink was made by the index of sensory evaluation.The main results were as follows:The main component of bacteria was lactic acid bacteria by 16S analysis which relative percentage was 75.25%;For fungus,yeast was the main component by 18S analysis and the relative percentage is 90.07%.Pichia was the main yeast at the genus level.By morphology,gram stain and catalase test,two strains of lactobacillus named L2 and L8 were found,both of them were identified as lactobacillus plantarum.Another two strains of fungus were also found which named Y2 and Y13,Y2 was identified as Pichia kudriavzevii while Y13 was Pichia guilliermondii.The strains were applied in the fermentation of papaya jiaosu and the results indicated that the optimal fermentation condition was papaya:granulated sugar=4:1(w/w);L2:L8:Y2:Y13=1:1:1:1;8%inoculation scale;temperature 30 ?.Several indexes were monitored in fermentation process and the result was as follows:the fermentation at inoculated condition was faster and acid content was higher than the fermentation at field condition.Also,the antioxidant capacity of the fermentation at inoculated condition was better than the fermentation at field condition.Papaya jiaosu contained more acid and less soluble solids compared with other jiaosu products and it had better antioxidant capacity.The formula was determined by orthogonal test.