Microbial Analysis of Produce Purchased from Florida Farmers’ Markets and Supermarkets

Introduction: The number of U.S farmers’ markets has increased by 41% since 2010, which can be attributed to the consumer demand for locally grown produce. However, data on the microbial quality of produce sold at farmers’ markets in Florida is lacking.

Purpose: The purpose of this study was to determine the prevalence of indicator organisms and pathogens in fresh produce from Florida farmers’ markets and supermarkets.

Methods: A total of 401 produce samples (115 tomatoes, 103 leafy greens, 106 berries, and 77 spinach) were collected from 9 farmers’ markets and 12 supermarkets in North and Central Florida (301 farmers’ market samples, 100 supermarket samples). Total coliforms and generic E. coli were analyzed using 3M E. coli/Coliform Count plates. Salmonella, L. monocytogenes, and E. coli O157:H7 were analyzed by real-time PCR assay kits.

Results: Total coliform presence was significantly higher (P <0.05) in farmers’ market leafy greens (75.6%) and spinach (59.6%) than supermarket leafy greens (52%) and spinach (24%), respectively. Generic E. coli was detected in 2.3% of farmers’ market produce, with none in supermarket samples. L. monocytogenes was detected in 3.9% and 2.6% of farmers’ market spinach and leafy greens, respectively. One farmers’ market tomato and one supermarket berry sample were positive for Salmonella. No E. coli O157:H7 was detected in this study.

Significance: The data from this study provides useful information on the microbiological quality of produce from farmers’ markets in Florida and may aid in the development of food safety programs for farmers’ markets or direct-to-consumer sales outlets.