Purpose: This project analyzed the microbial quality and safety of foods ordered online.
Methods: Three hundred forty-one perishable meat and seafood products were ordered from more than 80 online vendors, and delivered using common carriers including FedEx and UPS. The sampling strategy used cost of order, number of items available, and exclusion of low risk (e.g., canned) foods to maximize the number and variety of products analyzed. Data on food temperature on arrival was recorded. Foods were enumerated for the presence of indicator organisms including total plate count, coliforms and generic E. coli, and tested for the presence of pathogens including Salmonella, pathogenic E. coli, Clostridium perfringens, and Bacillus cereus. Seafood samples were tested for Vibrio parahaemolyticus, and Ready-to-Eat (RTE) samples were tested for Listeria monocytogenes and Staphylococcus aureus. Testing protocols were based on US Food and Drug Administration (FDA) Bacteriological and Analytical Manual (BAM) techniques.
Results: A total of 196 meat, 34 poultry, and 111 seafood samples were tested. Of these, 18.7% were positive for generic E. coli, 9.9% for pathogenic E. coli, 10.2% for Salmonella, 50.3% for B. cereus, 38.7% for V. parahaemolyticus and 18.2% for C. perfringens. More than 35% of the time foods were received at temperatures >4°C. A majority of E. coli, Salmonella and V. parahaemolyticus positive samples were received at temperatures >4°C. Amongst the 21 RTE samples tested, L. monocytogenes was detected in 4 samples. None of the samples tested positive for S. aureus.
Significance: This study characterizes the microbial risks associated with perishable foods ordered online. Foods are often received at temperatures >4°C and pathogen risk may be increased.