乳酸菌降解亚硝酸盐的技术研究
时间:2018-10-27 14:56 来源:毕业论文 作者:毕业论文 点击:次
| 摘要：食品中亚硝酸盐超标一直是人们广泛关注的一个问题，因此，如何除去亚硝酸盐一直是食品安全领域中热点课题之一，其中，探索生物法降解亚硝酸盐显得尤为重要。 本课题首先研究了短乳杆菌具有在亚硝酸盐毒性的环境下生存的能力，并且可以对其进行降解。其次对短乳杆菌的最适生长条件进行了研究，针对菌种接种量、培养温度、培养基pH、氯化钠添加量、不同碳源、不同葡萄糖浓度、不同氮源、静置培养与摇床培养这些方面进行了实验，得出以下结论：最适菌种接种量为10%，最适培养温度为37℃，最适培养基pH为5.62，最适氯化钠添加量为2％，最适碳源为葡萄糖，最适葡萄糖浓度为15g/L，最适单一氮源为酵母膏。不仅如此，短乳杆菌还进行了发酵罐发酵扩大菌种浓度后后对亚硝酸盐降解情况的实验研究。得出菌种扩大到发酵罐上控制pH生长初始生长速率不如不控制pH生长速率来得快，而当溶液pH小于4.14开始则是控制pH菌种生长速率快。而两者的亚硝酸盐降解量基本相差无几。29726 毕业论文关键词：亚硝酸盐；最适条件；降解；发酵罐；水中 Technology of nitrite degradation with Lactic acid Abstract： Excessive nitrite in foods has been an issue of widespread concern, Therefore, how to remove nitrite has been a subject of scientists,Among them, the method of nitrite degradation of exploration is very important. This subject first prove that Lactobacillus brevis can survive nitrite toxic environment , and can degrade nitrite.Secondly, the optimum growth conditions of Lactobacillus brevis were studied.For inoculated amount,culture temperature,medium pH,the amount of sodium chloride,different carbon sources,different concentrations of glucose,Different nitrogen sources,Stationary culture experiments conducted in these areas and shaker,concluded:Inoculated optimum amount of 10%,The optimum culture temperature is 37 ℃,The optimum medium pH 5.62,The optimum dosage of 2% sodium chloride,The optimum carbon source is glucose,The optimum concentration of glucose was 15g / L,Only optimum nitrogen source was yeast extract.In addition to this,Lactobacillus brevis was conducted experimental research on the degradation of nitrite after fermentor expand bacteria concentration.Obtain strains expanded to control pH on the growth fermenter initial growth rate is better not to control pH faster growth rate,When the pH is less than 4.14 , pH control bacteria growth rate is faster.The nitrite reduction is almost the same amount of both basic. Key Words：Nitrite；Optimal conditions；Degradation；Fermenter；Water 目录 1 绪论 1 1.1 引言 1 1.2 亚硝酸盐的来源以及对人体健康的危害 1 1.2.1 亚硝酸盐的来源 1 1.2.1.1 蔬菜中的亚硝酸盐 1 1.2.1.2 肉制品中的亚硝酸盐 2 1.2.1.3 水中的亚硝酸盐 2 1.2.2 亚硝酸盐对人体的危害 2 1.2.2.1 亚硝酸盐引起婴儿高铁血红蛋白症，俗称氰紫症 3 1.2.2.2 亚硝酸盐抵抗甲状腺素 3 1.2.2.3 亚硝酸盐致癌作用 3 1.2.2.4 亚硝酸盐引起智障 3 1.3 亚硝酸盐降解方法 4 1.3.1 物理和化学方法 4 1.3.1.1 蔬菜水果降解亚硝酸盐 4 1.3.1.2 茶多酚结合亚硝胺 4 1.3.1.3 竹叶抗氧化物清除亚硝酸盐的研究 4 1.3.2 生物降解法 5 1.3.3 酶处理法 5 1.4 本课题的研究目的与意义 5 (责任编辑：qin) |