常温和冷藏条件下鲜切西瓜中微生物生长研究

Study on microbial growth in fresh cut Citrullus lanatus under normal and refrigerated conditions

中文关键词:  鲜切西瓜  微生物  污染

英文关键词:fresh cut Citrullus lanatus  microorganism  contamination

中文摘要:

      目的 分析不同品种鲜切西瓜在常温和冷藏保存条件下微生物负载量随时间的变化规律。方法 选择市售较多的麒麟、甜王和黑美人西瓜30批次420份样品为研究对象, 对其进行切分处理后分别在常温和冷藏条件下保存2、4、6、8、10、12、24 h进行微生物项目检测, 得出菌落总数、大肠菌群计数、霉菌和酵母菌计数、金黄色葡萄球菌的微生物污染情况。结果 3个品种鲜切西瓜的菌落总数、大肠菌群计数、霉菌和酵母菌计数均随贮藏时间延长而增加, 麒麟、甜王和黑美人西瓜分别在常温保存8、10、12 h后菌落总数超过105 CFU/g, 保存8 h后大肠菌群计数超过100 CFU/g, 10 h后霉菌和酵母菌总数超过100 CFU/g; 冷藏条件下, 麒麟、甜王和黑美人西瓜保存8 h后平均菌落总数均超过104 CFU/g; 大肠菌群计数、霉菌和酵母菌计数均在保存10 h后超过100 CFU/g。金黄色葡萄球菌在常温保存4 h后被检出、冷藏保存6 h后检出, 总检出率32.86%。结论 鲜切西瓜在常温保存8 h后因微生物污染引起的安全风险增高, 消费者购买后应尽快食用, 如需保存尽量低温冷藏存储。

英文摘要:

      Objective To analyze the changes in microbial content of fresh cut Citrullus lanatus of different varieties over time under normal temperature and refrigeration storage conditions. Methods The 30 batches of 420 samples of the more popular of Kirin, Sweet King, and Black Beauty Citrullus lanatus, were selected as the research objects. After being divided and stored at room temperature and refrigerated conditions for 2, 4, 6, 8, 10, 12, and 24 hours, microbial item detection was carried out to obtain the total bacterial count, coliform count, mold and yeast count, and Staphylococcus aureus microbial contamination. Results The total bacterial count, coliform count, mold and yeast count of the three fresh cut Citrullus lanatus increased with storage time. After being stored at room temperature for 8, 10 and 12 hours, the total bacterial count of Kirin, Sweet King, and Black Beauty Citrullus lanatus exceeded 105 CFU/g, the coliform count exceeded 100 CFU/g after 8 hours, and the total number of mold and yeast count exceeded 100 CFU/g after 10 hours, under refrigeration conditions, the average total bacterial count of Kirin, Sweet King, and Black Beauty Citrullus lanatus stored for 8 hours exceeded 104 CFU/g; the coliform count, total number of molds and yeasts all exceeded 100 CFU/g after 10 hours of storage. Staphylococcus aureus was detected after 4 hours of storage at room temperature and 6 hours of refrigeration, with a total detection rate of 32.86%. Conclusion Fresh cut Citrullus lanatus pose an increased safety risk due to microbial contamination after being stored at room temperature for 8 hours. Consumers should consume them as soon as possible after purchase and store them at low temperatures if necessary.