Department of Food Science, Purdue University, West Lafayette, IN 47907, USA.
Department of Food Science, Purdue University, West Lafayette, IN 47907, USA.
Int J Food Microbiol. 2020 Sep 16;329:108685. doi: 10.1016/j.ijfoodmicro.2020.108685. Epub 2020 May 22.
Foodborne pathogens constitute a major food safety risk for cantaloupe, and pathogen biofilms formed are particularly difficult to remove. The goal of this study was to evaluate abrasive brushing in removing biofilms from cantaloupe surface using Listeria monocytogenes V7 and Salmonella enterica serovar Typhimurium ATCC 13311 as models. Cantaloupe rind pieces were inoculated and then subjected to 30 min or 24 h incubations. The incubated rind pieces were subject to different washing and/or brushing procedures and then the bacterial cells were enumerated. Cryo-SEM showed planktonic cells after 30 min incubation, whereas biofilms formed at rind surfaces after 24 h incubation. For L. monocytogenes 30 min incubation group, the log reductions were 1.4 for brushing, 2.1 for brushing with diatomaceous earth (DE), 2.8 for peroxyacetic acid (PAA) washing, 4.2 for brushing with PAA, and 4.0 for brushing with DE and PAA. In contrast, for the 24 h incubation group, the log reductions were 0.4 for brushing, 1.5 for brushing with DE, 1.1 for PAA washing, 1.6 for brushing with PAA, and 3.0 for brushing with DE and PAA. Similar results were observed for the S. Typhimurium group. These outcomes showed the pathogen-removal efficacy of brushing with DE (abrasive brushing) in the presence of biofilms, suggesting the potential application of abrasive brushing in cleaning cantaloupe for improved food safety.
食源性致病菌是哈密瓜的主要食品安全风险因素,而形成的病原菌生物膜尤其难以去除。本研究旨在评估使用李斯特菌和鼠伤寒沙门氏菌 ATCC 13311 作为模型,通过磨砂刷洗去除哈密瓜表面生物膜的效果。将哈密瓜果皮片进行接种,然后进行 30 分钟或 24 小时孵育。孵育后的果皮片进行不同的洗涤和/或刷洗程序,然后对细菌细胞进行计数。冷冻扫描电子显微镜显示,孵育 30 分钟后出现浮游细胞,而孵育 24 小时后在果皮表面形成生物膜。对于李斯特菌 30 分钟孵育组,刷洗的对数减少为 1.4,硅藻土(DE)刷洗的对数减少为 2.1,过氧乙酸(PAA)洗涤的对数减少为 2.8,PAA 刷洗的对数减少为 4.2,DE 和 PAA 刷洗的对数减少为 4.0。相比之下,对于 24 小时孵育组,刷洗的对数减少为 0.4,DE 刷洗的对数减少为 1.5,PAA 洗涤的对数减少为 1.1,PAA 刷洗的对数减少为 1.6,DE 和 PAA 刷洗的对数减少为 3.0。鼠伤寒沙门氏菌组也观察到了类似的结果。这些结果表明,在存在生物膜的情况下,DE(磨砂刷洗)对病原菌的去除效果较好,表明磨砂刷洗在清洁哈密瓜以提高食品安全方面具有潜在的应用前景。