Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 2/12/2013
Publication Date: 7/12/2013
Citation: Sheen, S., Lin, E., Hwang, C., Sommers, C.H. 2013. Temperature impact on the growth of Salmonella spp. in raw seafood. Meeting Abstract. IFT Annual Meeting, Chicago, IL., July 13-16, 2013.Volume 1,Page 1. Interpretive Summary:
Technical Abstract: In recent years, there has been foodborne illness outbreaks linked to the consumption of raw yellow-fin tuna contaminated with Salmonella. In this study, the growth behavior of Salmonella spp. on raw yellow-fin tuna fillet at temperatures 4 – 22 deg C was determined. The final cell population, lag phase, and maximum growth rate of Salmonella in tuna were obtained and used to develop predictive models. The maximum population of Salmonella in tuna stored at 22 deg C reached ca. 9 log CFU/g, while the population in tuna stored at 8, 12, and 16 deg C reached ca. 7 log CFU/g. There was no growth observed at 4 degree C. Salmonella in tuna stored at 8 deg C had a significantly longer lag phase (133 h) than those stored at 12 (12 h), 16 (10 h), and 22 deg C (6 h). The growth rates of Salmonella spp. in tuna increased from 0.052 - 0.231 log CFU/h as the storage temperatures rose from 8 - 22 deg C. The results were compared with those obtained from raw shrimp and significant differences were observed in these two seafood products. Regression models to predict the lag phase and growth rate of Salmonella spp. in tuna as a function of temperature were developed. The growth rate model predicts that the growth rate of Salmonella approaches 0 at around 6 degree C. Findings from this study illustrate the impact of temperature on the growth of Salmonella on raw tuna and provide useful and practical information for assessing microbial risk at refrigerated and abuse temperatures.