Abstract Survival of L. monocytogenes (LM) and shigatoxigenic Escherichia coli (STEC) during manufacture and aging of unpasteurized, farmstead-style cheese was investigated. Cheese produced with fresh, unpasteurized milk inoculated with a two-strain cocktail of LM and STEC (both ∼4.5 log cfu mL−1) was aged for 84 days at 4, 10, or 22 °C. Bacterial populations were assessed weekly. Pathogen populations were unchanged throughout cheese manufacture, but were significantly lower in whey than in curd. Aging at 4 °C caused a significant reduction in STEC and LM populations to below the enumeration limit on day 84. At 10 °C, a significant decrease in STEC was observed, but LM levels increased significantly; at 22 °C, populations of both pathogens increased. Regardless of aging temperature or time, both pathogens were detected in every cheese sample analyzed. Results suggest that aging cheese at the lowest temperature possible will provide the best control of STEC and LM.

中文翻译：

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农家式奶酪生产和陈化过程中单核细胞增生李斯特菌和产志贺毒素大肠杆菌的存活率

摘要 研究了未经高温消毒的农家式奶酪在制造和老化过程中单核细胞增生李斯特氏菌 (LM) 和产志贺毒素大肠杆菌 (STEC) 的存活情况。用新鲜的、未经高温消毒的牛奶生产的奶酪接种了 LM 和 STEC 的双菌株混合物（均为 ~4.5 log cfu mL-1），在 4、10 或 22°C 下陈酿 84 天。每周评估细菌种群。在整个奶酪制造过程中病原体种群没有变化，但乳清中的病原体数量明显低于凝乳。在 4 °C 下老化导致 STEC 和 LM 种群在第 84 天显着减少至计数限制以下。在 10 °C 下，观察到 STEC 显着减少，但 LM 水平显着增加；在 22 °C 时，两种病原体的数量都增加了。无论老化温度或时间，在分析的每个奶酪样品中都检测到两种病原体。结果表明，在尽可能低的温度下陈化奶酪将提供对 STEC 和 LM 的最佳控制。