Abstract Listeria monocytogenes is an important foodborne pathogen of particular relevance in “Ready To Eat” products. Food producers require rapid methods to detect L. monocytogenes, since the reference method (ISO 11290-1) is laborious, lengthy and costly. The aim of this study was to evaluate three alternative methods to detect L. monocytogenes in dry-cured ham following the ISO 16140-2:2016 standard: (A) impedance measurement followed by plating onto chromogenic agars; (B) impedance measurement followed by RNA hybridization, and (C) real-time PCR. Inclusivity and exclusivity were evaluated. The limits of detection 50 (LOD50) and the relative limits of detection (RLOD) were obtained by analysing dry-cured ham samples inoculated with L. monocytogenes at three different levels of contamination. The sensitivity study of alternative methods, as well as the relative specificity (SP), sensitivity (SE), and Kappa Cohen's index were calculated analysing 93 samples of sliced dry-cured ham. The inclusivity and exclusivity tests of three methods showed no interference in pathogen detection. LOD50 were very low for the three methods evaluated ( Methods A and C were considered to be a thoroughly appropriate control tool for use in the meat industry to improve the detection of L. monocytogenes.

中文翻译：

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阻抗测定法结合显色琼脂或 RNA 杂交和实时 PCR 方法检测干腌火腿中单核细胞增生李斯特氏菌的比较评价

摘要 单核细胞增生李斯特菌是一种重要的食源性病原体，与“即食”产品特别相关。食品生产商需要快速检测单核细胞增生李斯特菌的方法，因为参考方法 (ISO 11290-1) 费力、耗时且成本高昂。本研究的目的是评估按照 ISO 16140-2:2016 标准检测干腌火腿中单核细胞增生李斯特菌的三种替代方法：(A) 阻抗测量，然后接种到显色琼脂上；(B) 阻抗测量，然后是 RNA 杂交，和 (C) 实时 PCR。评估了包容性和排他性。检测限 50 (LOD50) 和相对检测限 (RLOD) 是通过分析在三种不同污染水平下接种单核细胞增生李斯特菌的干腌火腿样品获得的。替代方法的敏感性研究，以及相对特异性 (SP)、敏感性 (SE) 和 Kappa Cohen 指数是通过分析 93 个切片干腌火腿样品计算得出的。三种方法的包容性和排他性测试表明对病原体检测没有干扰。所评估的三种方法的 LOD50 都非常低（方法 A 和 C 被认为是用于肉类工业以改进单核细胞增生李斯特氏菌检测的完全合适的控制工具。