【作者】 贾莉；

【导师】 郝林；

【作者基本信息】 山西农业大学 ， 农产品加工及贮藏工程， 2003， 硕士

【摘要】 本试验对山西老陈醋浑浊沉淀进行了理化分析和微生学检测，分析了山西老陈醋浑浊沉淀形成的原因。筛选出高产酸性蛋白酶菌株H309，并用读菌株发酵制备粗蛋白酶制剂对山西老陈醋沉淀进行处理。结果如下： 1．山西老陈醋沉淀中蛋白质含76.18％，淀粉含5.3％，沉淀液中的细菌细胞数为2.60×10~6个／ml，细菌总数为34个／ml，挑取单菌落进行镜检大多数为芽孢菌，少数为其它细菌。原料分解不彻底和杂菌污染等是造成山西老陈醋浑浊沉淀的主要原因。 2．对曲霉属的H301，H302、H306、H307、H308、H309、H303-4-3菌株进行筛选，确定菌株H309产酸性蛋白酶能力最强，其产酶最适条件为：培养时间30h、培养温度30℃、PH4.5。酶作用的最适温度为50℃。试验中在最佳条件下测定该酸性蛋白酶制剂最高酶活达3027u／g。 3．用制备好的粗酶制剂按0.5％、1.0％、1.5％、2.0％、2.5％、3.0％、4.0％的添加量分别处理已有沉淀的醋样和刚下生产线的醋样，确定最佳添加量都为3.0％，距再次返浑的时间分别为49天和54天。分别比对照延长42天和44天。氨基态氮含量分别为0.343g／100ml和0.336g／100ml，分别比对照提高了28％和23％。处理后的醋样中细菌总数为600个／ml，符合GB2719-81，大肠菌群未检出。 4．用2％的海藻酸钠固定粗酶制剂，按添加3％的酶量处理刚下生产线的醋样。在多次分批处理中该固定化酶稳定性高，连续使用5个批次，凝胶珠基本完整不碎。醋样产生浑浊沉淀的时间平均为61天，比对照延长51天。用该法处理的醋液较游离酶制剂处理的澄清度高，且发生沉淀后沉淀量少，经长时间放置，沉淀量的增加不明显。更多还原

【Abstract】 The test analysed the cause of turbidity and sedimentation in Shanxi Super-Mature Vinegar, basing on physical and chemical analysis and microbiological detection on samples, and screened high-performance strain H309 of acid proteinase, and delt with the turbidity and sedimentation by coarse enzyme from H308 fermenting. Results as follows:One: Shanxi Super-Mature Vinegar contained protein 76.18%, amylum 5.3%, the cells number2.60 × lO⁶ per milliliter and bacteria amount 34 per ml , most of which were bacillus, a little of which were other bacteria , taking one colony to observe by speculum.The main cause leading to turbidity and sedimentation in Shanxi Super-Mature Vinegar were imperfect decomposition of crude materials and pollution of harmful strains.Two: The strain H309 was determined to be high performance of acid proteinase , as compared to H301,H302,H307,H309,H303-4-3,it’s fitness to situation: pH4.5, culture temperature 30℃, culture time 30h,most suitable temperature of enzyme function 50℃ .The highest enzyme unit was to be 3027u/mg under perfect situation.Three: Better additive amount of enzyme was 3.0% to sample₁ which had turbidity and sample₂ which has just been down-line .The time data of repeating sedimentation separately were 41d and 54d.Additive amount in test follows to 0.5%,1.0%,1.5%,2.0%,2.5%,3.0%,4.0%. In delt vinegar samples bacteria amount was 600 per m1 , no Escherichia Coli was found and ammonianitrogen date were 0.343g/100ml and 0.336g/100ml , as compared with control , separately 28% and 23% raised.Four: The vinegar samples just down-line was delt with immobilized coarse enzyme agent with Natrium alginate . The additive amount of enzyme accords to 3%. The stability of fixed enzyme was without apparently change after multiple batching. Gel pearls approximately remain former look after 5 continuous cycles . Average of repeating sedimentation in vinegar samples was 61 days , it’s 51 days longer than controls .The Vinegar juices delt with this way remain high clarity than those done with free enzyme , and which come out very light sedimentation ,and no evident addition after long storage.更多还原