The Research Of Risk Analysis Of L.Monocytogenes In Export CaiJuan

L.monocytogenes are a kind of food born pathogen that often reported in recent years, and listeriosis has already been a globe diseases. Listeria lives everywhere in environment, has already been a typical environmental sanitation matter. In recent years, ready-to-eat food's hazard of listeria has already brought the public attention for L.monocytogenes can grow and reproduce in low temperature. The export of CaiJuan takes a large proportion of all ready-to-eat export in YanTai, but the L.monocytogenes's risk bring the public attention as the increasing export.We have investigated the Listeria contamination of CaiJuan processing environments. We detected the Listeria contamination of the environment of the CaiJuan plant. And developed growth models, inactivation/ survival models of different conditions. Using these models and the export assessment of contamination of L.monocytogenes in CaiJuan and epidemic data and meal data, we developed a quantitative risk analysis report. And we propose some management measures to reduce the risk of human disease causing by eating CaiJuan.The results are this thesis as follows:1. This thesis studied the characteristic of L.monocytogenes, and finded out the range of L.monocytogenes growth NaCl concentration, pH and temperature. And the optimum NaCl concentration is 0～2%, pH is 6.0～9.0, temperature is 30～40℃;2. This thesis studied the growth trend of the L.monocytogenes at different temperatures, and developed growth models of L.monocytogenes in nutrient broth and CaiJuan at different temperatures. 37℃,35℃,30℃,25℃,15℃and the refrigeratory temperature in nutrient broth ,and 37℃,35℃,30℃,25℃,15℃in CaiJuan fitted by S curve and R value is higher.3. We have developed inactivation/survival models of L.monocytogenes in different conditions;4. We have investigated the L.monocytogenes contamination of CaiJuan processing environments, and detect the worst contamination in food plant;5. We studied the L.monocytogenes growth and inactivation data during the entire process of CaiJuan with mathematic models and some investigation data, and get a statistical data of risk of L.monocytogenes disease causing by eating a serve of CaiJuan;6. Aiming at the production of CaiJuan, we propose some management measures to reduce the risk of listeriosis causing by eating CaiJuan.