Text

theses

The widespread availability of the Internet has fostered the emergence of a new business sector: online sales of perishable foods. While there is an abundance of information available on safe food handling practices in homes, retail and foodservice establishments, the same can not be said for the handling of ‘mail-ordered foods’. This project used microbial techniques to identify bacterial foodborne pathogens and indicator organisms in foods ordered online. Randomly chosen food items were ordered from different online vendors. On arrival of the package containing the food, details such as the packaging materials used, temperature of food, presence of coolants etc. were recorded. Frozen samples were thawed at 2-5°C for no more than 18 hours. Food samples 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, Listeria monocytogenes, Clostridium perfringens, Bacillus cereus, Staphylococcus aureus, and Vibrio parahemolyticus. Testing protocols were based on US Food and Drug Administration (FDA) Bacteriological and Analytical Manual (BAM). A total of 341 samples were tested (196 meat, 34 poultry, 111 seafood). 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. parahemolyticus and 18.2% for C. perfringens. Also, on comparing incidence rates of food pathogens it was found that prevalence of Salmonella, B. cereus and V. parahemolyticus was higher in most of the mail-ordered foods than foods from other retail sources and prevalence of E. coli and C. perfringens was lower in most mail-ordered foods than foods from other retail sources. The temperature recorded on arrival of samples showed that majority of the coliforms, B.cereus, C. perfringens and L. monocytogenes positive samples were received at acceptable temperatures while E. coli, Salomonella and V. parahemolyticus were not at an acceptable temperature. Amongst the 21 Ready-to-eat (RTE) samples tested, L. monocytogenes was detected in 4 samples and none of the samples tested positive for S. aureus. In conclusion, this study illustrates the risks associated with online purchase of foods.

ETD_5197

M.S.

Includes bibliographical references

by Munira Agarwal

doi:10.7282/T3F47M7R

ETD graduate

The author owns the copyright to this work.