Submitted to: International Association for Food Protection
Publication Type: Abstract Only
Publication Acceptance Date: 3/23/2015
Publication Date: 7/25/2015
Citation: Hudson, L.K., Harrison, M.A., Berrang, M.E., Jones, D.R. 2015. Impact of alternative antimicrobial commercial egg washes on reducing Salmonella contamination. International Association for Food Protection. 78(Suppl A):183.
Technical Abstract: Introduction: Table eggs are washed with an alkaline detergent at approximately pH 11 and at a temperature at least 32°C, followed by a chlorine rinse. Both wash temperature and an antimicrobial rinse are required by regulation, but wash pH is not specified. At this pH, little, if any, free chlorine is available in the final rinse to act as an antimicrobial against pathogens like Salmonella. Using a chlorine stabilizer (e.g., T-128) in the wash may help maintain chlorine effectiveness. The heated wash warms eggs and slows the cooling process, which can encourage microbial growth. Objective: The objective was to determine the effectiveness four egg wash treatments to decrease Salmonella contamination: chlorine+T-128 at pH 6.0 at both ambient temperature or 49oC and alkaline wash at pH 11 at both ambient temperature or 49oC. All wash treatments were followed by a chlorine rinse. Methods: Eggs were drop inoculated with Salmonella Typhimurium and Salmonella Enteritidis, and were washed with each of the treatments. Two control treatments were also evaluated: inoculated, not washed and inoculated, washed with ambient temperature water. Post-wash Salmonella counts were compared to determine intervention effectiveness. Results: Salmonella counts were reduced by similar levels when washed with chlorine+T-128 at both temperatures and in the alkaline wash at the high temperature (~5 log CFU/mL egg shell emulsion reduction); these treatments were not significantly (p>0.05) different from each other. The counts were significantly (p<0.05) lower than the ambient temperature alkaline treatment and ambient water treatment counts (~3.2 log CFU/mL reduction). Significance: Results show that acidic washes may provide the same results as the traditional egg wash and that, for the acidic washes, ambient temperatures were just as effective as heated washes. Traditional basic egg washes do not to seem to show the same antimicrobial effectiveness when applied at ambient temperatures.