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This paper was to study microorganism contamination and proliferation status of touching substance and chilled carved pork on segmentation lead, separate and purify the spoilage microorganism in chilled carved pork, identify them by Biolog MicroStation System, study the initial microflora constitution of chilled carved pork, analyse the pattern of growth and decline, and penetrating situation of spoilage microorganism in chilled carved pork stored at 2±2℃, 10±2℃and 20±2℃. The results are as follows:1. The touching substance was contaminate due to carcass carrying microorganism, the touching substance microorganism increased as producing time extended, and microorganism quantity of conveyor increased to 1.89 ~ 2.48 log(cfu/cm~2) in1 hour, 2.63 ~ 3.18 log(cfu/cm~2) in 4 hour, microorganism counts of hands, tools, electric saws and chopping boards increased to 1.42 ~ 2.36log(cfu/cm~2) in 0.5 hour, then 1.84 ~ 3.08 log(cfu/cm~2) in 2 hour. Microorganism of initial chilled carved pork were detected mainly on the surface of chilled carved pork, which caused second contamination easily. Moreover, different microorganism counts were found in the different parts of chilled carved pork, such as surface and inside of microorganism count was 2.56 ~ 3.68 log(cfu/cm~2) and 3.18 ~ 3.97 log(cfu/g), respectively.2. Spoilage microorganism were incubated by selective medium, identificed by Biolog system, twelve strains bacteria were isolated and identified, four strains Enterbacteriaceae, two strain Pseudomonas, one strain Brochothrix thermosphacta, one strain Acinetobacter, two strains Lactobacillus, two strains Staphylococcus, seven strains gram-negative bacteria and five strains gram-positive bacteria in all.3. The initial total bacterial count was 3.33×104 ~ 4.53×104 CFU/g, initial microflora constitution were Enterbacteriaceae 8.47 ~ 12.96%, Pseudomonas 3.44 ~ 3.91%, Brochothrix thermosphacta 55.01 ~ 62.38%, Lactobacillus 15.07 ~ 29.80%, Staphylococcus and Micrococcus 0.61 ~ 2.90%, Mould and Yeast 2.64 ~ 3.26%.4. Brochothrix thermosphacta and Enterbacteriaceae and Pseudomonas were dominant spoilage microorganism of chilled carved pork stored at 2±2℃and 10±2℃, the proportion of Pseudomonas and Enterbacteriaceae in microflora constitution increased maximally, the amount of Pseudomonas increased maximally. Brochothrix thermosphacta and Enterbacteriaceae and Pseudomonas and Lactobacillus were dominant spoilage microorganism of chilled carved pork stored at 20±2℃, the proportion of Pseudomonas and Enterbacteriaceae in microflora constitution increased also maximally. 5. The initial total bacterial count of first to fourth layer of chilled carved pork stored at 2±2℃and 10±2℃, respectively difference two to three and two to three and one to two order of magnitude, respectively difference two to three and one to two and one to two order of magnitude at 20±2℃.6. The chilled carved pork stored at 2±2℃and 10±2℃, The size order of penetrating situation of different kinds of spoilage microorganism was Brochothrix thermosphacta > Enterbacteriaceae > Lactobacillus > Pseudomonas > Staphylococcus and Micrococcus > Mould and Yeast, The size order was Brochothrix thermosphacta > Enterbacteriaceae > Lactobacillus > Staphylococcus and Micrococcus > Pseudomonas > Mould and Yeast at 20±2℃.
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