SalmonellaPopulation Rebound and Its Prevention on Spray Washed and Non-washed Jalapeño Peppers and Roma Tomatoes in Humid Storage

Abstract

The potential of Salmonella population to rebound on non-washed and washed roma tomatoes and jalapeño peppers in humid storage at 4°C, 10°C, 15°C, 21°C, or 35°C for ≤12 days was investigated. The initial inoculation levels of Salmonella on peppers and tomatoes were 5.6 and 5.2 log CFU/cm(2), respectively. Air-drying of fruit surfaces resulted in contamination levels of 3.9 and 3.7 log CFU/cm(2) on inoculated peppers and tomatoes, respectively. At 21°C and 35°C, the levels of air-dried Salmonella inoculums on produce surfaces increased ≥2 log cycles, with the most rapid growth in the first 3 days. Mechanical washing on rollers (rinsing; R-treatment) or revolving brushes (rinsing and brushing; RB-treatment) with water decreased Salmonella counts by ≥2.5 log CFU/cm(2) on both peppers and tomatoes. After R- or RB-treatment, peppers stored at 21°C and 35°C permitted residual Salmonella (≤1.4 log CFU/cm(2)) to grow to 2.6-3.9 log CFU/cm(2). During storage, residual Salmonella (≤1.0 log CFU/cm(2)) on washed tomatoes increased to 3.1 log CFU/cm(2) at 35°C following R-treatment and 3.8 log CFU/cm(2) at 21°C following RB-treatment. Cold storage at 4°C and 10°C effectively prevented the proliferation of Salmonella on both washed and non-washed produce. The current study on jalapeño peppers and roma tomatoes demonstrated that Salmonella population can rebound on produce in humid storage before or after washing. The finding highlights the benefit of uninterrupted cold storage for safer produce operations.

Antimicrobial-Loaded Polymeric Micelles Inhibit Enteric Bacterial Pathogens on Spinach Leaf Surfaces During Multiple Simulated Pathogen Contamination Events

“…Antimicrobial treatments, nonetheless, reduced pathogens on treated samples, with geraniol-using treatments (GPN, UG) being more effective for reducing pathogen numbers as compared to HOCl and Control treatments. While the potential for multiple crosscontamination events should be low for produce packed and held in a sanitary environment, research has demonstrated the opportunity for post-harvest contamination of pathogens to occur even when sanitizing treatments are applied (Pao et al, 2012;Singh et al, 2018;Smolinski et al, 2018). This occurrence is one the FDA's final rule on produce safety aims to prevent by the mandatory application of food safety hazard reduction strategies (FDA, 2020).…”

Utilizing kitchen steamers to inactivate Listeria monocytogenes and Salmonella enterica on whole cantaloupe melons

“…Three non‐stem‐scar areas (~10 cm 2 each) were circle‐marked on each fruit. Each circled region was spot inoculated with 300 μl of each inoculum in ~20 droplets (Pao, Long III, Kim, & Rafie, ). Droplets were air‐dried for 2 hr at 22 °C before storage for ~22 hr at 4 or 22 °C to allow bacterial attachment.…”

Microbial ecology of fresh vegetables

“…Pre-storage of the tomatoes at 5 °C did not alter the growth kinetics compared to pre-storage at 22 °C (Table 17.2), suggesting that pre-storage temperature has lit tle impact on the growth of Salmonella once it is held at a higher temperature for storage after slicing. Conversely, storage at lower tempera tures (lower than 10 °C) suppresses Salmonella growth, and with longer storage times, a decrease in cell number may occur (Pao et al, 2012;Vandamm et al, 2013). Luo and others (2010) looked at fresh-cut romaine and iceberg lettuce inoculated with E. coli O157:H7 and resealed in bags containing the original O 2 levels.…”