Optimization of Fermentative Technic by Response Surface and Determination of Antioxidant Capacity of Grape-Rose Compound Strains Fermentative Beverage

In order to prepare a new type of compound strain fermentation drink,response surface method was used depends on compound strains' ratio,fermentative time and temperatures to optimize the fermentative technic and the antioxidant capacity of fermentation liquid was measured in vitro. The results showed,the addition of grape was 30%,rose was 0.75%,the ratio of compound strains was 5.5%:4.5% (GC:LP),the fermentative temperature was 33℃,the cost of fermentative time was 48 h,under this circumstance,total polyphenolic content would reach 9.92×10² mg/L,and got 92 in sensory score. Furthermore,under the action of compound strain fermentation,SOD activity reached 5.31×10³ U/L,DPPH radical scavenging activity reached 857 μmol/L and the anthocyanin content maintained 28 mg/mL. In addition,the fermentation process not only increased the sensory score but also improved the antioxidant capacity.