Abstract: Process parameters for the alcoholic fermentation of jujube juice prepared from Mu jujubes collected from Qingjian county such as initial solid content, yeast inoculum size, temperature and fermentation time were optimized using response surface methodology. Alcohol production was extremely significantly influenced by initial solid content, temperature and fermentation time (P＜0.01) and no significantly influenced by inoculum size (P＞0.05). Four process parameters were in descending order of their effects on alcohol production: fermentation time ＞ temperature ＞ initial solid content ＞ inoculum size. Their optimum conditions were determined to be 43 h, 31 ℃, 17% and 0.8%, respectively. Under these conditions, the alcohol concentration in fermented jujube juice was over 9.6%. The results of validation experiments demonstrated that the developed mathematical prediction model is applicable for practical production.

Key words: jujube, alcoholic fermentation, alcohol concentration, process parameters, response surface methodology