Angelidis Apostolos S, Koutsoumanis Konstantinos
Laboratory of Food Microbiology and Hygiene, Department of Food Science and Technology, Faculty of Agriculture, Aristotle University of Thessaloniki, Greece.
J Food Prot. 2006 Apr;69(4):938-42. doi: 10.4315/0362-028x-69.4.938.
The aim of this work was to estimate the prevalence and concentration of Listeria monocytogenes in packaged precut (slices or cubes) ready-to-eat (RTE) meat products available in the Hellenic retail market. Samples of these RTE meat products (n = 209) were taken from local supermarkets during a 3-month period and analyzed for the presence of L. monocytogenes with an automated enzymatic qualitative immunoassay followed by biochemical confirmation of positive results. The concentration of the pathogen in the positive samples was also determined. Seventeen samples (8.1%) were positive for L. monocytogenes. Eight (47.1%) of these 17 samples were from the same manufacturer; 36.4% of the products tested from this manufacturer were positive for L. monocytogenes. When bacon samples were not considered, the estimated prevalence of L. monocytogenes in sliced RTE meat products was much lower (3.1%). The L. monocytogenes populations in all positive samples were low, < or = 10 CFU/g. In 64.7% of the L. monocytogenes-positive samples, other Listeria species, including L. innocua and L. welshimeri, were also present at <10 to 690 CFU/g. These results indicate that L. monocytogenes is present in low numbers but is in a considerable proportion of the packaged precut RTE meat products that are sold in the Hellenic retail market. Cooked ham and bacon cut in cubes were the sample types most often contaminated with L. monocytogenes. The higher level of handling (e.g., cutting) associated with these products may further increase the risk of contamination with L. monocytogenes.
本研究旨在估算希腊零售市场上包装好的即食（RTE）预切（切片或方块）肉类产品中单核细胞增生李斯特菌的流行率和浓度。在3个月的时间里，从当地超市采集了这些即食肉类产品的样本（n = 209），并采用自动酶联定性免疫分析法检测单核细胞增生李斯特菌的存在情况，对阳性结果进行生化确认。还测定了阳性样本中病原体的浓度。17个样本（8.1%）单核细胞增生李斯特菌呈阳性。这17个样本中有8个（47.1%）来自同一制造商；该制造商检测的产品中有36.4%单核细胞增生李斯特菌呈阳性。如果不考虑培根样本，切片即食肉类产品中单核细胞增生李斯特菌的估计流行率要低得多（3.1%）。所有阳性样本中的单核细胞增生李斯特菌数量都很低，≤10 CFU/g。在64.7%的单核细胞增生李斯特菌阳性样本中，还存在其他李斯特菌属，包括无害李斯特菌和威氏李斯特菌，数量为<10至690 CFU/g。这些结果表明，单核细胞增生李斯特菌数量较少，但在希腊零售市场销售的包装好的预切即食肉类产品中占相当比例。切成方块的熟火腿和培根是最常被单核细胞增生李斯特菌污染的样本类型。与这些产品相关的更高程度的处理（如切割）可能会进一步增加单核细胞增生李斯特菌污染的风险。
