【作者】 骆旋；

【导师】 郭红卫；

【作者基本信息】 复旦大学 ， 营养与食品卫生学， 2010， 硕士

【摘要】 金黄色葡萄球菌是广泛分布于自然界中的一种食源性疾病病原菌。人们一旦食用被金黄色葡萄球菌污染的食物后就很容易发生食物中毒。由金黄色葡萄球菌引起的食物中毒在世界各国食物中毒暴发病例报告中均排名前列,已成为一个世界性的卫生问题。我国居民几乎每天都要食用各种猪肉产品。猪肉作为我国食用最为普通的肉类产品,由于含有非常丰富的营养成分,适宜金黄色葡萄球菌在其中生长繁殖,是金黄色葡萄球菌的重要污染源。因而开展猪肉产品中金黄色葡萄球菌风险评估就有着重要的意义。本课题以上海市居民作为目标人群,以现场调查的方式研究各种猪肉产品的膳食摄入情况,同时在市内各相关场所抽样检测了各种猪肉产品中金黄色葡萄球菌的污染现状。最后以居民购买猪肉为起点,最终食用为终点,参考国内外相关文献结合上述研究结果发展出一个新的倍数生长模型,估计6—10月在室温条件下储藏不超过1天时间最终食用时猪肉内的金黄色葡萄球菌含量,评价上海市居民因食用鲜猪肉而发生葡萄球菌食物中毒的风险。经过近二年的研究,最终结果如下：上海市居民平均每标准人日猪肉类产品的总摄入量为(107.77±5.95)g。猪内脏类产品的平均每标准人日总摄入量为(3.99±1.11)g,卤味熟食(的平均每标准人日总摄入量为(10.26±1.14)g,烟熏腊肉的平均每标准人日摄入量与卤味熟食差不多,为(9.70±1.20)g。400份抽检猪肉样品中共有370份金黄色葡萄球菌含量小于检测限10 cfu／g,占总样本数的92.5%。其中,6份样品为未检出,364份金黄色葡萄球菌含量低于检测限。阳性样品共有30份,检测浓度范围为10～6000 cfu／g,其中27份阳性样品的菌数含量低于1000 cfu／g,约占阳性样品数的90%。所有检测样品中金黄色葡萄球菌的平均污染水平几何均数值为—0.2998 log cfu／g。阳性样品中金黄色葡萄球菌的浓度几何均数为2.169 log cfu／g。风险评估结果显示6—10月食用时猪肉中金黄色葡萄球菌含量超过105 CFU／g的概率分别为3.3%、33.6%、21.4%、7.6%和0.3%。6、9、10月中初始污染水平与发生食物中毒风险的相关性最大,而在7、8月储藏时间与风险的相关性最大。7月通过食用猪肉发生葡萄球菌食物中毒的风险最大,接下来依次是8、9、6和10月。这一趋势与各月温度的分布基本一致,证明了温度越高越容易发生葡萄球菌食物中毒。更多还原

【Abstract】 Staphylococcus aureus is a food-borne pathogen widely distributing in nature. It is the top ranking causative bacreria of foodborne illness outbreaks in China and many other countries in the world which has become a worldwide health problem. As main animal foods, pork products are indispensable in Chinese residents’ daily dietary. It is easily contaminated by S.aureus because of its abundant nutritional components. So it is necessary to conduct a risk assessment to evaluative the risk associated with pork products contaminated with S.aureus.In this research, a field survey investigated the dietary intake of common pork products and an S.aureus contamination monitoring program of commercial pork products in Shanghai have been carried out. Meanwhile, multiple growth model was used to predict S.aureus growth under storing no more than 24 hours in room temperature for the time period of June through October.The results are as follows:The average consumption of total pork products in Shanghai urban citizens was 107.77g per reference man per day. The average consumption of pig tissues, cooked foods and smoking bacons were 3.99g,10.26g and 9.70g per reference man per day.There were 370 negative samples, account for 92.5%, including 6 samples in which S.aureus were not detected and 364samples in which bacteria number was below the detection limit.30 positive samples were detected at concentrations ranging from 10～6000 cfu/g, of which 27 samples were positive for bacterial counts lower than 1000 cfu/g, occupy 90%. The geometric mean of contaminated level in all 400 samples and positive samples were-0.2998 log cfu/g and 2.169 log cfu/g.The probabilities of occurrence of Staphylococcal food poisoning related to pork intake in June to October were 3.3%,33.6%,21.4%,7.6% and 0.3%. In June, September and September, contamination levels of S.aureus in pork at time of purchase was considered to be the most relative factor of Staphylococcal food poisoning which in July and August was most likely induced by consuming foods with long term storage. The distribution trend of illness probability in related five months was consistent with the temperature, suggesting that the prediction model used in our study is valid.更多还原