Fresh produce, as a known or suspected source of multiple foodborne outbreaks, harbors large populations of diverse microorganisms, which are partially released into wash water during processing. However, the dynamics of bacterial communities in wash water during produce processing is poorly understood. In this study, we investigated the effect of chlorine (FC) and peracetic acid (PAA) on the microbiome dynamics in spinach and romaine lettuce rinse water. Treatments with increasing concentrations of sanitizers resulted in convergence of distinct microbiomes. The resultant sanitizer resistant microbiome showed dominant presence by Bacillus sp., Arthrobacter psychrolactophilus, Cupriavidus sp., and Ralstonia sp. Most of the FC and PAA resistant bacteria isolated from spinach and lettuce rinse water after sanitation were gram positive spore forming species including Bacillus, Paenibacillus, and Brevibacillus spp., while several PAA resistant Pseudomonas spp. were also isolated from lettuce rinse water. Inoculation of foodborne pathogens altered the microbiome shift in spinach rinse water under PAA treatment, but not in lettuce rinse water or FC treated samples. These inoculated foodborne pathogens were not isolated among the sanitizer resistant strains.

新鲜农产品是多种食源性疫情的已知或疑似来源，含有大量不同的微生物，这些微生物在加工过程中部分释放到洗涤水中。然而，人们对农产品加工过程中洗涤水中细菌群落的动态知之甚少。在这项研究中，我们研究了氯 (FC) 和过氧乙酸 (PAA) 对菠菜和生菜冲洗水中微生物群动态的影响。增加消毒剂浓度的处理导致不同微生物组的融合。由此产生的对消毒剂具有抗性的微生物组显示，芽孢杆菌属、嗜冷乳节杆菌、铜绿菌属和拉尔斯通氏菌属占主导地位。从消毒后的菠菜和生菜冲洗水中分离出的大多数 FC 和 PAA 抗性细菌是革兰氏阳性芽孢形成菌，包括芽孢杆菌、类芽孢杆菌和短芽孢杆菌，而一些 PAA 抗性假单胞菌属。也从生菜冲洗水中分离出来。食源性病原体的接种改变了经 PAA 处理的菠菜冲洗水中的微生物组变化，但不会改变生菜冲洗水或 FC 处理的样品中的微生物组变化。这些接种的食源性病原体并未在消毒剂抗性菌株中分离出来。