Optimization of fermentation conditions for purple yam low- alcohol beverage and its ingredients analysis

The purpose of this study was to investigate the effect of the fermentaion conditions on the alcohol content and sensory properties of product of Purple yams.Then the fermentation conditions for purple yam low-alcohol beverage were optimized with response surface methodology. The results showed that the beverage was obtained after fermentation for 48 hours with 0.15% Angel wine strains SY dry yeast at 20 ℃ and p H3.70. The beverage was rich in active substances such as vitamins,anthocyanin,total flavonoids,total phenols,and allantoin.Under the optimal fermentation conditions,the purple yam low- alcohol drink contained sugar 3.50%,p H3.70,alcohol 2.52% and the score of sensory evaluation was 84.17. It was clear and transparent,deep red with strong aromas of purple yam and fermentation flavor.