Survival of Salmonella enterica, Escherichia coli O157:H7, and Listeria monocytogenes on Inoculated Walnut Kernels during Storage
Survival of Salmonella enterica, Escherichia coli O157:H7, and Listeria monocytogenes on Inoculated Walnut Kernels during Storage
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DOI：
10.4315/0362-028x.jfp-11-278
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发表时间：
2012-02-01
影响因子：
2
通讯作者：
Harris, Linda J.
中科院分区：
文献类型：
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作者：
Blessington, Tyann;Mitcham, Elizabeth J.;Harris, Linda J.
在核桃仁上评估沙门氏菌、大肠杆菌O 157：H7和单核细胞增生李斯特菌的单一菌株或混合物的存活率。用3至10 log CFU/g的病原体的水性制剂分别接种谷粒，干燥7天，然后在23 ℃下储存3周至1年以上。随着接种物干燥，观察到1至大于4 log CFU/g的快速降低。在某些情况下，在23摄氏度下储存的时间不影响细菌水平，在其他情况下，计算的沙门氏菌（每月0.05至0.35 log CFU/g）和大肠杆菌的下降率。coliO 157：H7（0.21 ~ 0.86log CFU/g/月）重叠，均低于计算的下降范围。单核细胞增多症（1.1至1.3 log CFU/g/月）。在一项单独的研究中，用4.2 log CFU/g的沙门氏菌肠道PT 30接种谷粒，干燥（最终水平，1.9 log CFU/g），并在-20 ℃、4 ℃和23 ℃下储存1年。沙门氏菌肠毒素PT 30在23 ℃下以每月0.10 log CFU/g的速度下降;储存时间对储存在-20 ℃或4 ℃下的玉米粒的水平没有显著影响。这些结果表明沙门氏菌的长期生存能力。E. coliO 157：H7和L.研究人员还对核桃仁上的单核细胞增多症进行了研究，并支持将这些生物纳入危害评估。
The survival of single strains or cocktails of Salmonella, Escherichia coli O157:H7, and Listeria monocytogenes was evaluated on walnut kernels. Kernels were separately inoculated with an aqueous preparation of the pathogens at 3 to 10 log CFU/g, dried for 7 days, and then stored at 23 degrees C for 3 weeks to more than I year. A rapid decrease of 1 to greater than 4 log CFU/g was observed as the inoculum dried. In some cases, the time of storage at 23 degrees C did not influence bacterial levels, and in other cases the calculated rates of decline for Salmonella (0.05 to 0.35 log CFU/g per month) and E. coli O157:H7 (0.21 to 0.86 log CFU/g per month) overlapped and were both lower than the range of calculated declines for L. monocytogenes (1.1 to 1.3 log CFU/g per month). In a separate study, kernels were inoculated with Salmonella Enteritidis PT 30 at 4.2 log CFU/g, dried (final level, 1.9 log CFU/g), and stored at -20, 4, and 23 degrees C for 1 year. Salmonella Enteritidis PT 30 declined at a rate of 0.10 log CFU/g per month at 23 degrees C; storage time did not significantly affect levels on kernels stored at -20 or 4 degrees C. These results indicate the long-term viability of Salmonella. E. coli O157:H7, and L. monocytogenes on walnut kernels and support inclusion of these organisms in hazard assessments.