Study On The Process Of Jujube Powder Fermentation

In this study, by using A-grade Hami Jujube from Xinjiang province as the subject,the fermentation process was optimized for the yeast strain isolated from jujube andCordyceps militaris, respectively. In addition, three drying methods were compared forthe fermentation products, as well as the content of phosphorus, calcium and ironbefore and after fermentation. The main results are as follows：1. By characterizing the appearance of yeast colonies and comparing their gasproduction capacity, a yeast strain was screened with strong fermentation capacity.2. By an orthogonal experiment with there factors including inoculum size,fermentation temperature and fermentation time each at there levels, the optimalfermentation conditions were determined as the inoculums size of7ml, thefermentation temperature of28°C and the fermentation time of104h.3. By an orthogonal experiment with there factors including inoculums size,fermentation time, feed/water ratio each at there levels, the optimal fermentationconditions were determined as the inoculum size of65ml, the fermentation time of3.5days and the feed/water ratio of1:0.45.4. Three drying methods for three types of jujube pulp, including hot air drying,spray-drying and vacuum freeze-drying, were evaluated with the content of vitamin C(Vc) as the main index and the moisture content, instant solubility and flavor as thesecondary indexes, indicating that the best drying method for jujube pulp was vacuumfreeze-drying, which had the highest Vc content, the lowest moisture content, goodinstant solubility and excellent flavor.5. The contents of Vc and elements including Ca, P and Fe were also determinedfor there types of three jujube as follows: the Vc content was48.5,50and54mg/100g;the pcontent was55,60and67mg/100g; the Ca content was61,65,70mg/100g; andthe Fe content was1.6,2.1and1.9mg/100g for unfermented jujube powder, and thejujube powder fermented by the yeast screened and Cordyceps militaris, respectively.6. By considering the intracellular or extracellular polysaccharides produced during the fermentation process by Cordyceps militaris and other indexes, thefollowing conclusions can be obtained: the jujube powder fermented by Cordycepsmilitaris is an excellent product with good quality, which possesses great marketpotential and is suitable for industrial production.