| The low temperature-heated meat products had a relatively short shelf life due to its low sterilization temperature and abundant nutrition which were propitious to spoilage microorganism growing and propagating. The spoilage discipline and mechanisms of low temperature-heated smoked and cooked sausage were summarized on the basis of spoilage bacteria isolation, identification and spoilage microflora analysis. The single preservative and biological inhibitors were chosen and the optimal proportion of the mixture of three kinds of preservatives was successfully investigated. The compound preservatives were proved effective by the meat industrial application. The two kinds of bio-preservative compounds prolonged the shelf life 13 days and 22 days when they were applied in meat products industry. The technology that bio-preservatives combined HACCP achieved low temperature bacteriostatic or bactericida. The results showed that the compound biological preservatives and HACCP had a promising application future in low temperature-heated meat products industry. The main results were as follows: 1.　The　total microbial number of low temperature-heated smoked and cooked sausage product was 1.5×102cfu/g. The main microflora survived after second sterilization was lactic bacteria, Pseudomonads and Bacillus. Lactic bacteria mainly came from material meat, natural casing, ADM concentrated protein, denatured corn starch and spice. Pseudomonads mainly came from meat. Bacillus mainly came from spice, denatured corn starch, material meat and natural casing. 2. Storage temperature had no significant effect on microflra component when the smoked and cooked sausages were stored at 7℃or 20℃. Diffent microflora multiplied during storage, while Bacillus increased most quickly. The main spoilage bacteria were isolated, purified and identified. The superior spoilage species were R1, R2, Y3, R4, R5, S1(R2), S2, S3, S4(Y3) and Y1. The inferior spoilage microorganisms were the species of Q3 and R3, the family of Q2 and Y2. 3. With the storage time extending of 7℃and 20℃, pH value all decreased and TVB-N value and TBARS value all increased at the early storage time, then decreased at the late stage. Storage temperature had no significant effect (P>0.05) on TBARS, while it had a significant effect (P<0.01) on pH, TVB-N and total microbial number. The shelf life of 7℃storage was double to 3 times of 20℃. 4. The main components of gas in gassy pouch of spoiled products were carbon dioxide, alkanes, keton and organic acid. 5. The biological Preservative1# and Preservative2# prolonged the shelf life 13 days and 22 days under the storage condition of 7℃, respectively. 6. HACCP system of smoked and cooked sausage processing was established. The critical control points were choice and receiving of material meat, repair, the second whipping, smoking and cooking, cutting, the second sterilization and checking of final products. 　The　creative　points　were　as　follows:　1. The spoilage microorganism of vacuum packing low temperature-heated smoked and cooked sausage was systematically studied in this research. The composition and distribution of spoilage microflora was investigated and the spoilage mechanisms of low temperature-heated smoked and cooked sausage during storage was pointed out. The results achieved in this study provided key data to other technology of microorganism control. 2. Two kinds of biological compound preservatives were successfully developed in this study. Preservatives1# and Preservatives2# prolonged shelf life 13 days and 22 days respectively when the low temperature-heated meat products were stored at 7℃. HACCP system was established and control measures were made. Part of study results were applied in low temperature-heated meat indusrial production. 3. The purring culture medium and numeration method was created as microbial inhibition trail. The microbial number survived was taken as standard to evaluate the inhibition effect of preservatives. The API and 16SrRNA identification method were applied in this research to identify spoilage microorganism, which was the new application of API and 16SrRNA technology in meat industry.
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