Department of Animal and Food Sciences, University of Delaware, Newark, DE 19716-2150, USA.
Department of Animal and Food Sciences, University of Delaware, Newark, DE 19716-2150, USA.
Food Res Int. 2019 Feb;116:778-785. doi: 10.1016/j.foodres.2018.09.011. Epub 2018 Sep 10.
In this study, we evaluated the performance of a large-scale decontamination system based on a washing process in combination with pulsed light (PL) exposure and HO/chlorine. In order to identify optimum processing condition, we first evaluated the effect of single and combined PL treatments on the inactivation of Salmonella on grape tomatoes using a small sample size of 50 g. Two inoculation methods, spot and dip, were used to simulate different contamination scenarios and two wash water quality, clear tap water and turbid tap water with extremely high levels of organic load and soil, were used to represent clean and very dirty wash water. In general, the combined PL-Chlorine and PL-HO treatments were more or as effective as chlorine washing in killing Salmonella on grape tomatoes and were able to keep residual Salmonella in wash water below the detection limit of 2 CFU/mL. The PL alone and combined PL-HO treatments were chosen and further tested for their decontamination efficacy under turbid wash water condition using large sample sizes, 300, 1000 and 2000 g. Sample size did not negatively affect the single and combined PL treatments on the inactivation of Salmonella on grape tomatoes. The combined PL-HO treatment in general showed better inactivation effect of Salmonella on tomatoes than the PL alone treatment. Additionally, the combined PL-HO treatment reduced Salmonella in turbid wash water below the detection limit of 2 CFU/mL in the majority of cases. In conclusion, the combined PL-HO treatment could potentially be used as an environmentally friendly alternative to chlorine washing for tomato decontamination and cleaning.
在这项研究中，我们评估了一种基于清洗工艺与脉冲光（PL）照射和 HO/氯结合的大规模去污系统的性能。为了确定最佳处理条件，我们首先使用 50g 的小样本量评估了单一和组合 PL 处理对葡萄番茄上沙门氏菌灭活的影响。采用点涂和浸泡两种接种方法，模拟了不同的污染情况，使用两种洗涤水水质，即清澈自来水和高有机负荷和土壤的混浊自来水，分别代表清洁和非常脏的洗涤水。一般来说，PL-氯和 PL-HO 联合处理在杀死葡萄番茄上的沙门氏菌方面与氯洗一样有效或更有效，并能使洗涤水中的残留沙门氏菌保持在 2 CFU/mL 的检测限以下。单独的 PL 和组合的 PL-HO 处理被选择，并在使用大样本量（300、1000 和 2000g）的混浊洗涤水条件下进一步测试其去污效果。样本大小并没有对单一和组合 PL 处理对葡萄番茄上沙门氏菌的灭活产生负面影响。一般来说，组合的 PL-HO 处理对番茄上沙门氏菌的灭活效果优于单独的 PL 处理。此外，在大多数情况下，组合的 PL-HO 处理将混浊洗涤水中的沙门氏菌减少到 2 CFU/mL 的检测限以下。总之，组合的 PL-HO 处理可能有潜力成为一种环保的替代氯洗的方法，用于番茄的去污和清洗。
