Conrad N. Hilton College of Hotel and Restaurant Management, University of Houston, Houston, Texas 77204-3028, USA.
J Food Prot. 2021 Jul 1;84(7):1169-1175. doi: 10.4315/JFP-20-406.
The number of farmers' markets registered by the U.S. Department of Agriculture has seen a significant increase, jumping from 1,755 in 1994 to 8,771 in 2019. Although previous studies have investigated the microbial profile of produce obtained from farmers' markets, literature exploring microbial (bacteria and virus) persistence on a variety of different farmers' market fomites over a 2-month period is limited. The objective of the current study was to investigate the persistence of key foodborne pathogens (Escherichia coli O157:H7, Listeria monocytogenes, Salmonella spp., Staphylococcus aureus, and MS2 bacteriophage) on these fomites by using a microbiological viability assay. The MS2 bacteriophage was quantified by using a host E. coli strain, and PFU were identified. A repeated measures analysis of variance was used to compare the persistence rates of foodborne pathogens on cardboard, plastic, tablecloth, molded pulp fiber, and wicker baskets used to store, transport, and display produce at farmers' markets. In general, molded pulp fiber, plastic, and wicker surface materials supported the persistence of foodborne pathogens the most, with Salmonella and S. aureus demonstrating the highest log concentrations over the longest period of time. Additionally, E. coli strains also persisted for a significant period of time on all fomites, with the exception of tablecloth. The results suggest that foodborne pathogens on these fomites pose a high risk of cross-contamination, particularly if the fomites cannot be washed, rinsed, and sanitized effectively (e.g., cardboard). The results highlight the need to avoid using porous, single-use storage containers, such as cardboard, molded pulp fiber, and wicker containers for extended periods of time and suggest the use of easily cleanable materials, such as plastic containers.
美国农业部登记的农贸市场数量显著增加，从 1994 年的 1755 个增加到 2019 年的 8771 个。虽然之前的研究已经调查了农贸市场农产品的微生物谱，但对于在两个月的时间内，各种不同农贸市场污染物上微生物（细菌和病毒）持久性的文献研究有限。本研究的目的是通过微生物存活能力检测来调查关键食源性病原体（大肠杆菌 O157:H7、单核细胞增生李斯特菌、沙门氏菌、金黄色葡萄球菌和 MS2 噬菌体）在这些污染物上的持久性。MS2 噬菌体通过宿主大肠杆菌菌株进行定量，并识别 PFU。采用重复测量方差分析比较食源性病原体在用于农贸市场储存、运输和展示农产品的纸板、塑料、台布、模压纸浆纤维和柳条篮上的持久性。总体而言，模压纸浆纤维、塑料和柳条表面材料最有利于食源性病原体的持久性，沙门氏菌和金黄色葡萄球菌在最长时间内表现出最高的对数浓度。此外，除了台布，所有污染物上的大肠杆菌菌株也能持续存在很长一段时间。结果表明，这些污染物上的食源性病原体具有很高的交叉污染风险，特别是如果污染物不能有效地清洗、冲洗和消毒（例如，纸板）。结果强调了需要避免长时间使用多孔、一次性储存容器（如纸板、模压纸浆纤维和柳条容器），并建议使用易于清洁的材料，如塑料容器。
