Quantitative Risk Assessment of Salmonella spp. in Fermented Pork Sausage (Nham)

Abstract

The Quantitative Microbial Risk Assessment (QMRA) of Salmonella spp. in fermented pork sausage, Nham, was carried out. It was to evaluate the public health impact of one of the favorite local foods on Thai people from exposure to Salmonella spp. The QMRA employed secondary data available from published papers and articles from government agencies in Thailand. Salmonella spp. was the major cause of gastroenteritis in Thailand. The most frequently found strains are S. Entertidis and S. Typhimurium. It was found that probability of Salmonella contaminated in Nham was 0.186. The probability of Salmonella prevalence in Nham was 0.035. The average value of Salmonella found in Nham ranged 105 to 195 CFU/25g. However, the amount of Salmonella in raw pork was 205-250 CFU/25g with the probability of 0.045. It appeared that the number of Salmonella decreased when the raw pork was processed to Nham which has the low pH of 4.5. The maximum contamination level of Salmonella in Nham was 20% with the range of 10-40%. Nham, stored at 4^oC for 14 days, had Salmonella increased to 10 to 10⁵ /piece or 1 to 500 CFU/g. The risk of becoming ill due to the consumption of Nham was 1.9% if one consumes Nham with Salmonella of 120-170 CFU/25g. It is recommended to cook Nham before consumption to reduce the risk.