99D-31 |
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M. A. MUNDO, H. Lee, O. I. Padilla-Zakour, and R. W. Worobo. Food Science & Technology, Cornell Univ., New York State Agricultural Experiment Station, 630 W. North St., Geneva, NY 14456-1371 Honey has demonstrated antibacterial activity in vitro against many foodborne bacteria. If its activity is retained in food systems, it holds potential as a natural food preservative. Our objective was to determine the efficacy of honey’s antibacterial activity in minimally processed foods, to improve their safety and/or extend shelf-life. Four raw honeys with known levels of hydrogen peroxide antibacterial activity were applied to raw ground turkey, hot-dogs, fresh apple cider and apple slices. Shelf-life and challenge studies were conducted using synthetic honey and sterile water as controls. For shelf-life studies, uninoculated food samples were cut and stored in sterile stomacher bags or centrifuge tubes at 7°C. 5% honey was added and mixed. Triplicate samples were evaluated for total aerobic plate count and yeast and molds on days 0, 3, 7, 10, and 14. For challenge studies, foods were prepared as previously described, but inoculated with 10 ?l of 105 bacterial culture/10 grams or milliliters of food prior to honey addition. Escherichia coli O157:H7 and Salmonella Typhimurium were both separately added to apple slices, cider, and turkey; Listeria monocytogenes was added to hot-dog slices. Twice weekly samples were enumerated for pathogen levels using differential media. Best results were obtained with apple cider and hot-dogs. Salmonella in apple cider and Listeria in hot-dogs were significantly reduced in the presence of select antibacterially active honeys. The efficacy was higher in cider than in apple slices due to better mixing. Furthermore, Listeria counts for samples containing honeys with high or medium levels of hydrogen peroxide activity were lower than the hot-dogs with other honeys or water. Honeys with medium to high levels of hydrogen peroxide antibacterial activity could be useful in preserving foods, but the food’s physical properties and the level of antibacterial activity must be considered for successful microbial inhibition.
Session 99D, Food Microbiology: General
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