The Detectiontion And Research Of Main Microorganisms In Meat Products

In this thesis, low-temperature meat products and traditional cured meat products that are popular in markets were studied. We selected several kinds of meat products that were representative and had the largest market share from different manufacturers, including crispy sausage, black beef, smoked ham, which represent low-temperature meat products; and bacon that represents cured meat products. Through simulating market environment and simulating the fluctuation of temperature, we studied the bacteria composition and fluctuation of main microorganisms during storage and marketing, understood the microbial species, distribution and amount in low-temperature meat products and cured meat products, and detected pathogenic microorganisms in relevant samples. The aim of this experiment is to evaluate the security of meat products during processing, transportation and marketing. It can be targeted to develop quality control measures that are conducive to the protection of meat safety and improve the technical level of the meat processing industry.The experimental results are as follows:(1) The total plant counts of several kinds of low-temperature meat products did not exceed the national standards within the shelf life. There was no serious pollution. The microbial indicators of meat product under (6-10)℃were significantly higher than those under (0-4)℃, low temperature could effectively inhibit microbial growth.(2) The total plant count of bulk bacon that hung under room temperature declined, which closely related to water volatilizing during storage. The total plant count of vacuum-packed cured meat that stored at room temperature was more than 1.5×106 within the shelf life, especially, the total plant counts in two kinds of products increased significantly from 120 days to 150 days. There was no obvious corruption when they stored near shelf life.(3) The main bacteria in low-temperature meat products was Lactobacillus, followed by Bacillus, as well as a small amount of Pseudomonas, aureus and Micrococcus. The main bacteria in traditional cured meat (bacon) were Staphylococcus aureus and Micrococcus, followed by Bacillus, lactic acid bacteria and Pseudomonas.(4) By classic identification of microorganisms morphological, physiological and biochemical identification methods, the bacteria isolated from the smoked ham samples were Bacillus coagulans, Bacillus licheniformis, Leuconostoc mesenteroides, Lactobacillus sake, Lactococcus lactis, Staphylococcus saprophyticus. The bacteria isolated from black beef samples were Lactobacillus sake, Bacillus licheniformis, Lactobacillus parabuchneri, Mali Lactobacillus, Lactobacillus curvatus, Leuconostoc mesenteroides and Pseudomonas fluorescens.The main bacteria isolated from the crispy sausage were Lactobacillus curvatus, the inulin Bacillus Lactobacillus, Leuconostoc mesenteroides, Brinell Lactobacillus, Lactobacillus fermentum, Lactobacillus brevis, Lactobacillus fermentium, and Pseudomonas fluorescens.(5) The main bacteria isolated from the bacon were meat aureus, epidermal aureus, Staphylococcus saprophyticus, Lactococcus lactis, Lactococcus lactis, Lactobacillus curvatus, Leuconostoc mesenteroides, Bacillus subtilis, Bacillus licheniformis, Bacillus coagulans.(6) After the screening of suspicious strains and the use of API biochemical reagents:API Listeria, API Staph, API 20E, L.monocytogenes, Staphylococcus aureus, Shigella, Salmonella were not detected in all low-temperature meat products and cured meat (bacon) product samples, which demonstrated that the samples meet national standards of pathogens.