Study On The Production Process Of Jujube Vinegar

"Lang Jia Yuan" dates produced in the area of Chaoyang, Beijing, is a breeding species from the wild date. The fruit size of the neat uniform, medium sized, oval cylindrical, bilaterally symmetrical, the average single fruit weight 7.36g, fruit size and tidy uniform. Its very thin and brittle skin, thick red, uniform color, smooth and glossy; flesh pale green, crisp texture, delicate, juicy, sweet and sour jujube rich, quality superior. In this study, "Lang Jia Yuan" date for the raw materials, working in the acetic acid fermentation product, through fermentation and chemical analysis of modern technology to improve the efficiency of acetic acid fermentation and vinegar flavor quality of the core, of the jujube vinegar brewing process. Jujube vinegar fermentation stage is divided into stages of alcohol fermentation and acetic fermentation stage. Main contents and results:(1) "Lang Jia Yuan"date with the other two dates of Beijing, the nutrient content, the results are as follows:all Nutrient content measured in water, total sugar, reducing sugar, crude fat, total acid, trace elements are "Lang Jia Yuan" dates> "Chang Xin Dian" dates> "Jing Nan"date; crude fiber, total ash are"Chang Xin Dian" dates> "Jing Nan" White dates>"Lang Jia Yuan" dates; pectin content is the"Lang Jia Yuan"dates> "Jing Nan" White dates> "Chang Xin Dian" dates. and measured "Lang Jia Yuan" dates nutrient composition:moisture 48.2%, total sugar,32.2%,17.6%sugar,2.45%of total cellulose, pectin 0.5%, crude fat 130.3mg/100g, Vc content of 3.8mg/g, protein 0.4%, total acid 1.35%,2.46%total ash,Ca210μg/g, Fe 53.8μg/g, Mg 300μg/g, K 800μg/g.(2) The impact of culture on the results of the four main factors and their interactions range of the best level of research and study conducted by response surface analysis methods were optimized culture conditions to get better training conditions:temperature 30℃, medium with initial pH 5.8, liquid volume 95mL/250mL and the inoculation volume of 3.6%. Culture conditions and 3 times as parallel test, verification test results, the measured absorbance value of 1.676±0.03.(3) Chosen for the fermentation broth suitable sterilization method, sterilization is 100℃20min, while adding 50ug/L concentration of potassium sulfite to inhibit the growth of bacteria; choose the appropriate initial fermentation of sugar concentration 14%.On the impact of fermentation temperature, inoculum size, initial pH, NaHSO3 add volume, add the amount of nitrogen source and yeast species age do single factor experiments. Factors determine the appropriate values are:temperature 26℃,4%inoculum, initial pH6, NaHS03 addition of 60mg/L, and 0.65%added nitrogen source and the best time of yeast inoculation 10h.Finally, by Plackett-Burman experimental analysis derived fermentation temperature, yeast inoculum, initial pH for the fermentation of the significant factors in alcohol fermentation; and through orthogonal optimization and the optimum fermentation parameters for the fermentation temperature 24℃, inoculum 6%, the initial pH5.(4) acetic acid fermentation stage:the basis of single factor experiments, response surface method by fermentation temperature, the initial alcohol, acetic acid bacteria inoculum was optimized to optimize the results:the best point in the fermentation temperature 32.141℃; 5.222%inoculum; initial alcohol content 6.01%.(5) The best formula is derived jujube jujube vinegar 14%,10%of jujube juice, citric acid 150mg/100mL, sucrose 10%. Jujube vinegar drink and draw the best way to clarify:95℃heating 2 min, cooled 2%diatomaceous earth filtration; best sterilization methods 95℃10min, and testing of finished products and microbial indicators of physical and chemical indicators are in line with GB18187-2000 and GB2719-2003 standards.