Optimization Of Apple Cider Vinegar Fermentation Process And Analysis On Organic Acids And Antioxidants

Based on the yeast and acetic acid bacteria strains and raw materials of Fuji apple in gansu JingNing, the experiment on single and mixed strains fermented performance test was done, as for the research on strains of the comprehensive evaluation performance and fermentation condition optimization and enlargement. Meanwhile, the organic acid of each samples by reverse phase HPLC were deteced and the change trend of characterized organic acid during the fermentation process of apple vinegar were also analyzed.Through testing the apple cider vinegar antioxidant content and main content, with its DPPH free radicals of the clearance as evaluation indexes, the apple cider vinegar antioxidant capacity were evaluated.The results showed that, compared with single strains,the mixed strains has better ability of the leaven microzyme fermentation, the mixing ratio of 2-1 with 1751 and 1383 plant, can show the optimal fermentation characteristics, acetic fermentation performance is good strains for acid bacilli 20064.Compared with 500ml triangle bottle fermentation , 15L fermentation tank with electronic monitoring and record on temperature, speed, pH, dissolved oxygen can better response to characteristic indexes of fermentation process of change. During the alcoholic fermentation, yeast having higher conversion and faster growth than a triangle bottle fermentation can achieve expected 24h ahead of sugar and alcohol content, the transformation is thoroughly. Acetic fermentation stage, the fermentation can be finished in 96h because of its tong oxygen fully and higher activity of acetic acid bacteria, total acid (with apple products plan) content of acid 55.6 g/L.The organic acid was detected in sample has acetic acid, butanedioic acid, malic acid, lactic acid, citric acid, tartaric acid, oxalic acid. malic acid and tartaric acid content of apple juice is higher and account for 65.9% of and 26.2% of total organic acids, respectively; malic acid, lactic acid, succinic acid content of Apple wine is higher and account for 26.02%,17.45% and 40.00% of total organic acids; While acetic acid, lactic acid, succinic acid content of apple cider vinegar account for 90.54%, 4.69%, and 3.58% of total organic acids, respectively. During Apple cider vinegar fermentation , malic acid, tartaric acid content gradually decline, lactic acid, acetic acid, succinic acid content increase, while the content of oxalic acid and citric acid change little.The content of total polyphenol ,VC and flavonoid in Apple cider vinegar was 2.14 mg/ml, 2.19 mg/ml and 2.73 mg / 100ml respectively, its concentration can reach 92.37% for 200 mu g/ml DPPH radical clearance .Total phenol, the flavonoids content and DPPH free radicals clearance have higher correlation, correlation coefficient 0.8758 and 0.8723, respectively. therefore, phenolic and flavonoid can be as a evaluation index for apple cider vinegar oxidation resistance.