风干肠中挥发性化合物分析及产香菌的筛选鉴定

发布时间：2018-02-09 17:53

  本文关键词： 风干肠 挥发性化合物 3-甲基丁醛 葡萄球菌　出处：《黑龙江大学》2012年硕士论文　论文类型：学位论文

【摘要】：哈尔滨风干肠是一种传统的中式自然发酵香肠,广受消费者喜爱。为了解风干肠加工过程中挥发性化合物的组成和来源,本试验使用固相微萃取-气质联用(SPME-GC/MS)技术分析检测哈尔滨风干肠各加工阶段和各种辅料的挥发性化合物,发现其变化规律、探索其形成机理。然后使用选择性培养基从自然发酵风干肠中分离纯化葡萄球菌,按照发酵剂筛选标准筛选出优良葡萄球菌,并对其中产3-甲基丁醛的菌株进行鉴定,最后研究产香葡萄球菌的产香能力和机理并考察发酵肉制品生产工艺参数对其生长的影响。试验结果表明：(1)分别从腌制后样品、日晒后样品和风干发酵后样品中鉴定出19、20、30种挥发性风味化合物。整个加工过程中鉴定出的挥发性化合物共有34种,主要风味化合物是柠檬烯,苯乙烯,己醛,乙醇,己酸乙酯和2-戊酮,同时还检测并鉴定出了3-甲基丁醛。这些挥发性化合物的生成可能归因于添加的酒、香辛料、脂肪氧化、氨基酸代谢、微生物活动及这些因素之间的相互作用。混合香辛料、姜粉、白酒中分别鉴定出49、48、12种挥发性化合物。(2)从自然发酵风干肠样品中分离出46株革兰氏阳性葡萄球菌,按照发酵剂筛选标准对其进行筛选并考察其产3-甲基丁醛能力,得到2株符合条件的优良葡萄球菌S18和S44。经形态学、API Stap生化鉴定和16S rDNA分子生物鉴定,S18为木糖葡萄球菌(Staphylococcus xylosus), S44为缓慢葡萄球菌(Staphylococcus lentus)。(3)鉴于在发酵肉制品中木糖葡萄球菌为常用发酵剂菌种,故对本试验得到的木糖葡萄球菌S18产3-甲基丁醛的能力和途径进行了探讨,发现在模型系统中木糖葡萄球菌S18代谢亮氨酸产3-甲基丁醛的速度及产量均优于亮氨酸与核糖的Maillard反应,表明在风干肠中3-甲基丁醛的主要来源可能为微生物的作用。在模型系统中无论是否添加5’-磷酸吡哆醛,木糖葡萄球菌S18均能产3-甲基丁醛,说明木糖葡萄球菌S18可能通过氧化和转氨途径生成3-甲基丁醛。(4)发酵肉制品生产工艺参数对木糖葡萄球菌S18的生长有一定的影响。pH5-8的环境中,S18能够生长,最适pH为7；在17-37℃条件下,该菌能够生长,在此范围内温度高则生长旺盛；在添加0-5%食盐的培养基中S18生长良好;S18能在添加0-150ppm亚硝酸盐的培养基中生长,但100ppm以上的亚硝酸盐浓度对菌株的生长有一定的抑制作用。
[Abstract]:Harbin air-dried sausage is a traditional Chinese natural fermented sausage, which is popular with consumers. In order to understand the composition and source of volatile compounds in the processing of air-dried sausage, In this experiment, SPME-GC / MS was used to analyze and detect volatile compounds in various processing stages of Harbin air-dried intestines and various auxiliary materials. To explore its formation mechanism, Staphylococcus was isolated and purified from naturally fermented air-dried intestine by selective culture medium, and the excellent staphylococcus was screened according to the screening criteria of starter, and the strains producing 3-methylbutyraldehyde were identified. Finally, the aroma producing ability and mechanism of Staphylococcus aureus were studied, and the effects of technological parameters on the growth of fermented meat products were investigated. Thirty volatile flavor compounds were identified in sunburn samples and air-dried fermenting samples. 34 volatile compounds were identified in the whole processing process. The main flavor compounds were limonene, styrene, hexanal, ethanol, limonene, styrene, hexanal, ethanol, limonene, styrene, hexaldehyde, ethanol, and the main flavor compounds were limonene, styrene, hexaldehyde and ethanol. Ethyl caproate and 2-pentanone were also detected and identified. The formation of these volatile compounds may be attributed to the addition of wine, spices, fat oxidation, amino acid metabolism, 46 strains of Gram-positive Staphylococcus were isolated from naturally fermented air-dried intestine samples. According to the screening criteria of starter, the ability of producing 3-methylbutyraldehyde was investigated. Two excellent strains of Staphylococcus staphylococcus S18 and S44were obtained by morphological Stap and 16s rDNA molecular biological identification. S18 was Staphylococcus xylosuschus and S44 was Staphylococcus lentus.3) in view of the xylose grape in fermented meat products. Cocci is a common starter strain, Therefore, the ability and way of producing 3-methylbutyraldehyde from Staphylococcus xylostaphylococcus S18 were discussed. It was found that in the model system, the rate and yield of leucine production from leucine of Staphylococcus xylostaphylococcus S18 was better than that of Maillard reaction between leucine and ribose. It is suggested that the main source of 3-methylbutyraldehyde in air-dried intestine may be the action of microorganism. In the model system, Staphylococcus xylostaphylococcus S18 can produce 3-methylbutyraldehyde whether or not it is added with or without 5-pyridoxal phosphate. It is suggested that the production process parameters of fermented meat products may have a certain effect on the growth of Staphylococcus xylostaphylococcus S18 by oxidation and ammonia transfer. The optimum pH was 7; at 17-37 鈩，

本文编号：1498518