P3-68 Microbiological Profile and Incidence of Salmonella spp. on Cherry Tomato 

Wednesday, July 12, 2017
Exhibit Hall (Tampa Convention Center)
Marla Leal-Cervantes , Universidad Autónoma de Querétaro , Querétaro , Mexico
Sofia Arvizu-Medrano , Universidad Autónoma de Querétaro , Querétaro , Mexico
Montserrat Hernandez-Iturriaga , Universidad Autónoma de Querétaro , Querétaro , Mexico
Nanci E. Martínez-Gonzáles , Departamento de Farmacología, CUCEI, Universidad de Guadalajara , Guadalajara , Mexico
Introduction:  Cherry tomato has become popular in the gourmet market due to its consumption as an ingredient in fresh salads. Unfortunately, a recall in 2012 related to the presence of Salmonella on cherry tomatoes and an outbreak in 2013 associated with the same pathogen in the United States of America, created an alert regarding the safety of the fruit. Information about the microbial risk at which people could be exposed by consuming cherry tomato is scarce. 

Purpose: The objective of this study was to determine the microbiological quality including incidence of Salmonella spp. on cherry tomatoes at points of sale.

Methods:  Samples of cherry tomatoes were collected from four supermarkets (157) and four local markets (83) from Querétaro, México. Fruit (50 g) were analyzed to quantify aerobic plate counts (APC), coliforms, molds/yeasts, and Escherichia coli; Salmonella presence was also investigated in 50 g samples. All microbiological analysis was done using Bacteriological Analytic Manual (BAM) methods. Nonparametric comparisons of microbial populations were carried out using the Wilcoxon-Kruskal-Wallis test. 

Results:  Populations of microbial indicator were higher in samples collected from local markets (P<0.05). Median values of APC, coliforms and molds/yeasts on tomatoes from supermarkets and local markets were 3.58 and 5.10, 1.02 and 1.52, 3.21 and 4.76 log CFU/g, respectively. Escherichia coli was present on samples from supermarkets (4.5%) and local markets (16.9%) at low levels (0.09 to 0.69 log MPN/g). Salmonella spp. was also detected in 16.6% (26 of 157) and in 8.4% (7 of 83) of the tested samples from supermarkets and local markets, respectively.

Significance:  The presence of Salmonella was higher in tomatoes from supermarkets despite the fact that E. coli, an indicator of fecal contamination, did not reflect the same trend. This data set could be helpful to understand the risk for consumer’s health associated with Salmonella and cherry tomatoes.