冰鲜鸡肉，是指严格执行兽医检验检疫制度，对屠宰后的禽胴体进行迅速冷却处理，使胴体温度迅速降为0-4℃，并在后续加工、流通和销售过程中始终保持0-4℃范围内的生鲜鸡肉。加工冰鲜鸡肉消耗能源少、成本低，但销售价格高，它不仅保持了原有的色泽和香味，更保持了冻鸡肉解冻时易流失的营养成份，口感、风味与新鲜度等都优于冻鸡肉，且食用方便，避免了冻品食用前的解冻过程，深受消费者欢迎。但是，冰鲜鸡肉货架期短。因此，在屠宰、分割、冷藏、运输和销售一系列过程中关注冰鲜鸡肉的微生物污染状况，采取有效的措施减轻污染程度并防止二次污染，对于保证产品安全卫生、延长产品货架期有着重要的意义。 本研究在某大型肉鸡屠宰企业取样，采用传统培养技术和分子技术相结合的方法分析冰鲜鸡肉在低温低氧分压贮藏条件下菌相变化趋势，并确定优势腐败菌。分析肉鸡屠宰加工过程中不同操作点微生物数量及种类变化情况，确定关键控制点。研究不同化学减菌剂对优势腐败菌的保鲜抑制作用，再根据栅栏技术对几种化学减菌剂进行复配，得到复配减菌剂的浓度的最优比，找到一种实用有效的化学减菌剂配方。 1．应用基于16SrDNA的变性梯度凝胶电泳指纹图谱技术（DGGE）对冰鲜鸡肉微生物多样性进行研究。分别取鸡胸肉和鸡腿肉贮藏0d，3d，5d，7d和9d的样品，提取样品总DNA，通过PCR扩增、变性梯度凝胶电泳，将16SrDNA(V6-V8区)的PCR扩增片段割胶测序确定样品中的微生物群落，与传统培养方法结果进行比较。传统培养方法结果表明：鸡胸肉和鸡腿肉在低温低氧分压条件下贮藏，导致腐败的优势腐败菌相差不明显，且变化趋势相一致；DGGE指纹图谱结果表明，初始污染数量较多的微生物不一定是优势腐败菌，能适应低温低氧分压的微生物最终成为优势腐败菌，且鸡胸肉和鸡腿肉的优势腐败菌有一定差异。传统培养技术和DGGE割胶测序所得优势腐败菌的菌相不完全相同，综合两种不同研究方法，确定冰鲜鸡肉优势腐败菌为乳酸菌，肠杆菌，热杀索丝菌，腐败希瓦氏菌，毗邻颗粒链菌和肉杆菌。 2.采用变性梯度凝胶电泳指纹图谱技术研究肉鸡屠宰加工过程中不同操作点微生物的污染情况，以确定关键控制点。分别采取肉鸡屠宰加工过程中胴体表面、工人手表面、预冷池中的水、空气中的样品以及真空包装贮藏过程中样品，然后进行DGGE指纹图谱分析。结果表明：肉鸡的屠宰加工过程包括浸烫脱毛、倒挂、去内脏、冷却和分级包装，不同处理会对肉鸡胴体表面的污染微生物产生不同的影响，去内脏后肉鸡胴体表面微生物的种类和数量都有所增加，但预冷能有效减少肉鸡胴体表面微生物的种类和数量，空气中微生物数量随着生产时间的延长不断增加，这些操作点也成交叉污染的地方，尤其工人手表面是引起交叉污染最主要的原因。 3. 几种化学减菌剂对冰鲜鸡肉的减菌作用，主要包括两方面内容：1、应用单 因子试验配制五种不同的化学减菌剂，用浸泡方式对肉样进行处理，以菌落变化数为指标，确定各化学减菌剂的减菌效果，2、利用四因子三次正交旋转设计，探讨乳酸，醋酸，磷酸钠和酸化亚氯酸钠复合减菌剂最优比，并确定各种化学减菌剂在复配中所起的作用。结果表明：乳酸，醋酸，次氯酸钠，磷酸钠和酸化亚氯酸钠对优势腐败菌都有一定的抑制作用，但抑制效果不一样。在乳酸，醋酸，酸化亚氯酸钠，磷酸钠四种减菌剂优化设计时，乳酸对优势腐败菌的影响最大，酸化亚氯酸钠作用最小，乳酸，醋酸，磷酸钠，酸化亚氯酸钠在编码值范围内菌落数对数值均有最小值，磷酸钠加入量的变化对复合化学减菌剂的减菌效果影响最大，最佳浓度比为乳酸的浓度为1.598%，酸化亚氯酸钠的浓度为0.07683%，磷酸钠的浓度为8.732%和醋酸的浓度为1.805%。

Fresh chicken,is the strict implementation of veterinary inspection and quarantine system, the carcass of slaughtered poultry processing for rapid cooling, so that the carcass temperature is quickly reduced to 0-4 ℃, and in the subsequent processing, distribution and sales process always keep 0-4 ℃. The processing of fresh chicken consume low energy and low cost, but selling price is high.It has a bright prospect because of the advantages over frozen chicken on nutrition, flavor and sanitation. But the shelf life of fresh chicken is short.We concerns microbiological contamination of fresh chicken during a series of slaughtering, cutting, cold storage and transportation, take effective measures to reduce microbiological contamination, it is significante guarantee product safety and health and extend product shelf life. This study take samples from a large chicken slaughtering enterprise, Study on the microbial community structure of refrigerated storage of fresh chicken was studied by PCR amplification and denaturing gradient gel electrophorsis based 16S rDNA, and clearly know dominant spoilage bacteria. The number and types of microorganisms change during broiler slaughter processing,and determine the critical control points. Different chemical substances were used to inhibit dominant spoilage bacteria, to find a practical and effective chemical reduction formula. 1. The microbial community structure of refrigerated storage of fresh chicken was studied by PCR amplification and denaturing gradient gel electrophorsis based 16S rDNA.Activated sludge samples were collect from both chicken breast and drumstick.The total DNA was extracted and 16S rDNA was amplified by universal primer, The mocrobial community structure was analyzed by denaturing gradient gel electrophoresis,compared with the traditional culture. The traditional culture showed that: dominnat spoilage bacteria there are no differences between chicken breast and drumstick,and two curves changing trends are the same. The DGGE pattern showed that initial microflora counts are more is not the dominant spoilage bacteria,micro-organisnms can adapt to the environmentis are the dominna spoilage bacteria,chicken breast and drumstick of dominnat spoilage bacteria have some differences.The dominant spoilage bacteria of traditional culture and DGGE are not exactly the same,combination of two different approaches, determine the dominant spoilage bacteria of fresh chicken are Lactic acid bacteria, Enterobacter,Brochothrix thermosphacta, Shewanella putrefaciens,Granulicatella adiacens and Carnobacterium sp.. 2. This study was designed to identify the critical control point during broiler slaughter by exploring the microbial diversity in the produce of broiler slaughter using polymerase chain reaction ·denaturing gradient gel elec-trophoresis(PCR-DGGE). In stage of broiler slaughter，the contamination microbia was sampled from broiler carcasses surface, the surface of workers’ hand, the water in the pre-cooling pool, the air and broiler longissimus muscles of postmortem broiler carcasses, which was vacuum packaging at 4℃ for 7 day. The results indicated that the processing of different treatment in the process of broiler slaughter will have different effects on microbial contamination of carcass surface, the type and number of microbia have increased after the broiler carcass to the visceral, however, the type and number of microbia have reduced after pre-cooling, microorganisms in the air increase in production, these operating points are also into areas of cross-contamination, in particular, the surface of workers’ hand is the main reason causing cross-contamination. 3. Several chemical substances were used to preservation of fresh chicken, the research including two aspects:1, Fresh chicken were dipped respectively in various chemical solution after division, reducing microflora counts determine to the best chemical solution.2,The essential of Sodium phosphate, acetic acid, lactic acid and acidified sodium chlorite were screened as significant inhibition on dominant spoilage bacteria, and optimum combination the four chemical solution for inhibition dominant spoilage bacteria was evaluated by the three levels of four factors quadratic rotation design.The results showed that sodium hypochlorite, sodium phosphate, acetic acid, lactic acid and acidified sodium chlorite were screened have significant inhibition on dominant spoilage bacteria. Lactic acid were more positive than that of Sodium phosphate, acetic acid,and acidified sodium chlorite, lactic acid, acetic acid, sodium phosphate and acidified sodium chlorite in the range of coded have the minimum values, dominant spoilage bacteria change with the rate of adding sodium phosphate is fastest,the results of regression analysis showed that the optimum proportion of combination of lactic acid, acetic acid, sodium phosphate and acidified sodium chlorite was1.598%, 1.805%,8.732%,0.07683%.