【作者】 徐静；

【导师】 马长伟；

【作者基本信息】 中国农业大学 ， 食品科学， 2004， 硕士

【摘要】 本研究在前人研究的基础上，从自然发酵香肠和自制腌肉中分离、筛选适用于肉制品发酵的乳酸菌菌株，并进行了初步的鉴定，分析了这些菌株的微生物学特性、产酸产酶特性，并对它们在发酵香肠和发酵肉中的应用进行了初步的研究，试验结果表明： 依据适用于发酵肉制品的乳酸菌菌株的筛选标准。从自然发酵香肠和自制腌肉中分离筛选出两株性能优良的乳酸菌菌株C67和R6，它们不产气不产生粘液，产酸及耐盐耐亚硝性能良好，经过初步鉴定，皆为干酪乳杆菌。 菌株C67在液体MRS培养基中培养10小时时菌体密度达到最大，R6培养12小时时菌体密度达到最大，是菌体的最佳收获时期。C67和R6在24小时内最低pH值分别为4.00，3.97，在25.40℃范围内可较好的生长。 两株菌具有微弱的蛋白酶活性，都没有脂酶活性，不能降解组氨酸和赖氨酸生成相应的组胺和尸胺。 本试验在发酵香肠的生产过程中检测了产品的理化和微生物指标，并进行了感官评价。发酵组产品的pH、Aw和水分含量比对照组下降的速度快，最终的结果低，蛋白水解指数大，POV值低，AV无明显区别。发酵组中的乳酸菌一直是优势菌，最大值为10~8cfu／g，而对照组中的乳酸菌逐渐增加到10~7cfu／g。发酵组比对照组在感官上具有更浓郁的发酵滋气味，酸味柔和，适合中国人的口味，但美中不足的是表面颜色比对照组差，这是由于单菌发酵的缺陷所致。 本试验还对发酵肉的生产工艺进行了初探。在发酵肉的生产过程中检测了产品的理化和微生物指标，并进行了感官评价。发酵组产品的pH、Aw、水分含量较对照组低。发酵组中乳酸菌一直是优势菌，最大值为10~8cfu／g，对照组中的乳酸菌是逐渐增加到10~6cfu／g。发酵组比对照组在感官上具有明显的发酵特性，酸味可以接受。更多还原

【Abstract】 In this research, strains were isolated and screened from natural fermented sausages and cured meat. Their capacity of acid and enzyme production , their application in fermented sausages and fermented meats were analysed. The results were:Based on the standards of screening lactic acid bacteria) for fermented meat products, Two strains of lactic acid bacteria with excellent character were isolated and screened from natural fermented sausages and cured meat, respectively named as C67 and R6. They did not produce gas and slime,showed high acidification rate and acidification capacity.Both of them also showed high resistance to nitrite and NaCl.They were identified as Lactobacillus casei.The optimum harvest time of maximum bacteria counts of C67 in MRS broth was 10h,that time of R6 was 12h.The lowest pH within 24hours in MRS broth of C67 and R6 were respectively 4.00 and 3.97.They grew well at 25-40℃.They did not produce lipase and had weak proteolytic activity.They could not produce the biogenic amines from histidine and lysine.Physico-chemical properties and microbiological characteristics were studied during the processing of fermented sausage,sensory analysis was also done. The results showed that the pH ,Aw, moisture content dropped more rapidly and with higher proteolysis index in the groups added strains than those in the control group.There were no differences in acidity value and peroxide value between three groups. POV of two fermented groups was lower than control groups.The lactic acid bacteria of fermented groups was dominant flora during the whole processing with the maximum bacteria counts 108cfu/g, while that of the control group increased gradualy with the maximum bacteria counts 107cfu/g.The fermented groups had more welcome flavor and sour. They are suitable for Chinese people.But the surface colour of the fermented groups were worse than the control group.There were faults in single strain fermentation.Physico-chemical properties and microbiological character were studied during the processing of fermented meat,sensory analysis was also done. The results showed that the pH ,Aw, moisture content dropped more rapidly than the comtol.The lactic acid bacteria of fermented groups was dominant flora during the whole processing with the maximum bacterial number 108cfu/g, while that of the control group increased gradualy with the maximum bacterial counts 106cfu/g. The fermented groups had obvious fermentation flavor and acceptable sour.更多还原