89D-3 |
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S. MIN, L. J. Harris, and J. M. Krochta. Dept. of Food Science & Technology, Univ. of California, Davis, 1 Shields Ave., Davis, CA 95616-8598 Antimicrobial edible films and coatings have received attention as a new means to control post-processing contamination of foods with Salmonella and E. coli O157:H7. Application of antimicrobial-containing edible films has advantages over the direct application of antibacterial agents, because films and coatings can be designed to slow antimicrobial diffusion from the surface of food. The objectives were to 1) evaluate initial antimicrobial effects of whey protein isolate coatings incorporating lactoperoxidase systems (LPOS-WPI coatings) against Salmonella or E. coli O157:H7 inoculated onto roasted turkey, 2) study the effect of LPOS-WPI coatings on the growth of Salmonella or E. coli O157:H7 on roasted turkey during storage, and 3) compare the antimicrobial activities of the LPOS-incorporated coating with direct spreading of a LPOS solution.Initial antimicrobial effects of LPOS-WPI coatings were examined with various inoculation levels and LPOS concentrations. LPOS-WPI coating solutions were applied to the surface of roasted turkey before or after inoculating with 5-strain cocktails of S. enterica or E. coli O157:H7. A storage study was conducted with Salmonella- or E. coli O157:H7-inoculated turkey for 42 d at 4 and 10°C. Turkey samples for the storage study were inoculated before or after application of the LPOS-WPI coating or LPOS solution spreading. LPOS-WPI coatings at 5% and 3% of LPOS demonstrated initial 2-log CFU/g reduction of Salmonella or E. coli O157:H7, respectively. This effect was observed regardless of whether the turkey was inoculated before or after coating. Populations of Salmonella and E. coli O157:H7 continued to be inhibited over the 42-day storage period. More effective inhibition was obtained with the LPOS-WPI coating when compared to spreading the LPOS solution. LPOS-WPI coatings show potential for inhibiting microorganisms already present on ready-to-eat meat products, as well as for the control of microbial growth from contamination after coating of the food product.
Session 89D, Food Microbiology: Antimicrobial effects on foodborne microorganisms
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |