【作者】 高洁；

【导师】 王晓闻；

【作者基本信息】 山西农业大学 ， 农业硕士（专业学位）， 2018， 硕士

【摘要】 本文主要以酸浆果为实验原料,利用适宜的乳酸菌进行发酵,旨在找到酸浆发酵果汁的最佳发酵工艺。实验研究结果如下:(1)酸浆发酵果汁适宜发酵菌种的选择及菌种配比优化:根据不同乳酸菌48 h内的乳酸含量、pH值、活菌数的变化情况,确定了酸浆果原汁由嗜酸乳杆菌(La)和植物乳杆菌(Lp)进行发酵。根据两种乳酸菌间不同比例的复配实验,确定复合菌发酵比例 La:Lp 为 2:1。(2)乳酸菌发酵酸浆果原汁工艺优化:以乳酸含量为主要指标,通过单因素和响应面实验确定了酸浆发酵果汁最佳发酵工艺为:接种量10%,发酵温度37℃,发酵时间 20 h。以感官评定为主要指标,对发酵后的酸浆果汁进行风味调配。通过单因素和正交实验,确定了酸浆发酵果汁β-环糊精添加工艺为:在20℃下,添加0.01%的p-环糊精,搅拌30 min。阿斯巴甜、安赛蜜、果葡糖浆、柠檬酸的添加量为:阿斯巴甜0.04%,安赛蜜0.02%,果葡糖浆8%,柠檬酸0.03%。通过分层情况以及感官评定确定酸浆发酵果汁中黄原胶的添加量为0.1%,发酵果汁口感顺滑,无结块。(3)酸浆发酵果汁活性成分测定及抗氧化性研究:本实验测定了酸浆发酵果汁中多酚、黄酮以及维生素C的含量,分别为0.1mg/mL,0.6mg/mL,0.15mg/mL。通过对五种指标的测定,比较了两种果汁的抗氧化性。结果表明:经过乳酸菌发酵后的酸浆果汁的抗氧化性增强。(4)酸浆果原汁经乳酸菌发酵后,新生成了 21种风味物质。其中酯类、酚类物质减少,醛类、烯类、酸类、酮类物质增加。通过对酸浆发酵果汁贮藏定性的研究,根据其在4℃和26℃下的pH值、黏度、离心沉淀率、可溶性固形物及其卫生指标的变化,得出酸浆发酵果汁在4℃下储藏效果较优。更多还原

【Abstract】 This article mainly studies on the production process of fermented juices,with tested materials of Physalis and jujube,as well as finds the best fermentation condition for Physalis-jujube beverage.The experimental results are as follows:(1)The optimal fermentation strain and ratio study of Physalis-jujube beverage.The optimal strain and ratio are obtained through the change of lactic acid content,pH value and viable count of different lactic acid bacteria within 48 hours.The optimal fermentation strain are Lactobacillus acidophilus(Ld)and Lactobacillus plants(Lp).According to the compounding experiments with different proportions between the two kinds of lactic acid bacteria.The optimal fermentation ratio was La:Lp 2:1,and these had a cooperative fermentation capability.(2)The optimal fermentation conditions study of Physalis-jujube beverage.The optimal formula is obtained through single factor and response surface experiments.The best fermentation conditions are inoculation amount 10%,fermentation temperature 37℃ and fermentation time 20h.Sensory evaluation was used as the main indicator to adjust the flavor of fermented juice.Through single factor and orthogonal experiments,the best embedding process for fermented juice was adding 0.01%β-CD at 20℃ and stirring for 30 min.Aspartame,acesulfame K,fructose syrup,and citric acid were added in amounts of 0.04%,0.02%,8%and 0.03%.Through layering and sensory evaluation,the optimum amount of xanthan gumthe was 0.1%,and the fermented juice was smooth and no agglomeration.(3)Study on Active Components and Antioxidant Activity of Physalis-jujube beverage.This experiment measured the content of polyphenols,flavonoids and vitamin C in fermented juices,which were 0.1mg/mL,0.6mg/mL,0.15mg/mL.Five different methods were used to compare the antioxidant properties of the two juices.The results showed that anti-oxidation of fermented juice stronger than the puree·(4)Twenty one kinds of flavoring substances were newly generated in fermented juice.Among them,esters and phenols decline,and aldehydes,vinyls,acids and ketones increase.The compound beverage is stored at 4℃ and 26℃ respectively comparing its changes of pH,viscosity,centrifugation precipitating rate,soluble solids and hygienic indicator.The opital storage condition of compound beverage at 4℃.更多还原