Researcn On Microbial Community Diversity And Successional Law For Chilled Meat Of Tan Sheep

At the beginning of the 21st century, consumption of muslin food developed rapidly in whole worl d. Especially, the consumption and trade of muslin meat commodities made thousands of million dollar s every year. With the largest amount of muslin people in China, Ningxia has its advantage on Islamic c ulture. And muslin meat commodities present the commonness of religions principles to people who be lieve in Islam. So, exporting frozen and fresh Ningxia lamb to Middle East area plays an important role in Ningxia Muslim Food Industry Programming. In common sense, the lag of the processing theory an d short preservation time restricted the export. This paper introduces the microbial flora diversity; abun dance and community structure during the storage of Ningxia sheep, by using the technology of macro genomics combine with the traditional quality index, detecting community structure and its variation wi th time changes, determining dominant microorganisms at various stages during storage of Ningxia she ep. By discussing about the anglicizing relationship between the changes of nutrient metabolism and co mmunity succession, revealing inner driving mechanism of community succession, and elaborating prin ciple of freshness preservation technology, it has a very important theoretical guiding significance on re forming production technology and transportation. The results are as follows:Determining total number of colonies, pH and TVB-N values the time extended in the chilled mea t of Tan sheep of cold storage at 0℃.The results showed that the total bacterial count was consistent wit h the change of TVB-N value, and showed a trend of gradual increase,and on the tenth day increases ra pidly, indicating meat spoilage.In the first 8 days, the pH of the cold fresh Tan lamp remain in the 5.6-6. 2 range, at the beginning of the emergence of a downward trend and began to rise after sixth days, at te nth days pH reached more than 6.2 then meat began to appear rotten, tenth days later pH rapidly increas ed and on twelfth days the meat has been completely modified.Analysising the microbial flora diversity, abundance and community structure of Tan sheep with b arcoded pyrosequencing during the storage at 0℃, identifying the dominant bacteria in each period.Ele ven Bacteriophyta was detected with the sequencing from the amplified template pieces through the bri dge PCR. With the increase of storage time, the bacterial diversity and abundance of the chilled meat of Tan sheep was increased. Proteobacteria, Firmicutes, unclassified_Bacteria, Actinobacteria, Cyanoba cteria/Chloroplast and Acidobacteria together constitute the main structure of the cold fresh Tan lamp. Proteobacteria and Firmicutes are the dominant bacteria in the cold fresh Tan lamp.In addition to the main flora, other classification bacteria abundance are low, and even some of the gate level appeared o nly a few sequences number, the percentage of the share is less than 0.01%.These results indicate that Bacterial has the characteristic is diversity rich, abundance concentration. On the zeroth day, Pseudom onas, Acinetobacter, Exiguobacterium and Aeromicrobium as the dominant bacteria in the cold fresh T an lamp. On the fourth day, the Pseudomonas grew rapidly, from the initial 8.86% to 26.23%, and beca me the dominant bacteria at this time. Brochothrix thermosphacta, Psychrobacter, Acinetobacter, Esch erichia has a certain growth.On the eighth day, the Pseudomonas and Brochothrix thermosphacta occu py the absolute advantage, and become the dominant bacteria. When fungus was stored for the first day, the total number of yeast accounted for 76.14% of the total number of fungi, the number of mycete wa s less than yeast. And the number of yeast increased over time, it is always the dominant fungi in the pr ocess of Tan sheep storage.The selective culture method was used to isolate and purify the dominant bacteria and fungi isolat ed from the previous chapter.The results show that the dominant bacteria were Pseudomonas, Acinetob acter, Aeromicrobium, Exiguobacterium in the initial storage.The dominant bacteria on the forth day w ere Pseudomonas, Brochothrix thermosphacta, Escherichia and Clostridium. Until eighth days, Brocho thrix thermosphacta grew rapidly and become the dominant bacteria both with Pseudomonas.