Optimization of ethanol and bioactive compounds fermentation of Elaeocarpus hygrophilus Kurz by using response surface methodology

Abstract

Elaeocarpus hygrophilus Kurz is used for food such as jam, lactic fermentation, picking with rice wine, etc. To enhance the value and contribute to product diversification of Elaeocarpus hygrophilus, the optimizing wine fermentation by response surface methodology (RSM) was conducted with 2 factors including initial total soluble solids (20 -30oBrix) and pH (3.5-4.5). The 3-level factional design used for optimizing the effect of initial total soluble and pH were in agreement with the quadratic regression models well with R2 >0.85. Based on the response surface plots, the optimal parameters of fermentation were 23oBrix and pH 4.4. In the optimized condition, the ethanol content of E. hygrophilus wine was 7.33 % v.v-1 . In 100 g of dry matter, the content of phenolic, flavonoid and tannin in wine was 0.47 g TAE, 0.20 g QE and 1.67 g TAE, respectively.