Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD 20740, USA.
Food Microbiol. 2009 Dec;26(8):932-5. doi: 10.1016/j.fm.2009.06.005. Epub 2009 Jun 12.
Francisella tularensis is a Gram-negative bacterium that can cause gastrointestinal or oropharyngeal tularemia in humans from ingestion of contaminated food or water. Despite the potential for accidental or intentional contamination of foods with F. tularensis, there are few studies on the long-term survivability of this organism in food matrices. Infant formula has previously been implicated as a vehicle for the transmission of a variety of bacterial pathogens in infants. In this study, we investigated the survival of F. tularensis in dehydrated infant formula under various storage conditions. F. tularensis was stored for up to 12 weeks in dehydrated infant formula in an ambient air, dry or nitrogen atmosphere. Viable counts of fresh F. tularensis at 12 weeks in infant formula revealed a 4.15, 3.37 and 3.72-log decrease in ambient air, dry and nitrogen atmosphere, respectively. D-values were calculated (in weeks) as 3.99, 4.68 and 4.47 in air, dry and nitrogen atmosphere, respectively.
弗氏志贺菌是一种革兰氏阴性菌，可通过摄入被污染的食物或水在人类中引起胃肠道或口咽型土拉菌病。尽管食物中存在意外或故意污染弗氏志贺菌的可能性，但关于该生物体在食物基质中的长期生存能力的研究很少。婴儿配方奶粉以前曾被认为是多种细菌病原体在婴儿中传播的媒介。在这项研究中，我们研究了弗氏志贺菌在各种储存条件下在脱水婴儿配方奶粉中的存活情况。弗氏志贺菌在环境空气、干燥或氮气气氛中在脱水婴儿配方奶粉中储存长达 12 周。在婴儿配方奶粉中，新鲜弗氏志贺菌在 12 周时的活菌计数分别下降了 4.15、3.37 和 3.72 个对数。在空气、干燥和氮气气氛中的 D 值（以周为单位）分别为 3.99、4.68 和 4.47。
