|Huang, Chi-yun - National Taiwan University|
|Sheen, Lee-yan - National Taiwan University|
Submitted to: Food Control
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/4/2017
Publication Date: 1/2/2018
Citation: Sommers, C.H., Huang, C., Sheen, L., Sheen, S., Huang, L. 2018. Growth modeling of uropathogenic Escherichia coli in ground chicken meat. Food Control. 86:397-402.
Interpretive Summary: Interpretive Summary: Extraintesinal Pathogenic Escherichia coli (ExPEC), including Uropathogenic E. coli (UPEC), are common contaminants in poultry meat. ExPEC and UPEC are associated with conditions such as inflammatory bowel disease, ulcerative colitis, Crohn’s Disease, and Urinary Tract infections which affect millions of people each year at an economic cost of ca. $20 billion. Predictive microbiology (e.g. growth modeling using a mathematical equation) is used to assess the risk of bacterial pathogens to human health. A complex mathematical equation was developed to describe the growth of UPEC in ground chicken meat at 4, 10, 15, 22 and 30 deg C. Our results indicate the growth behavior of UPEC is similar to generic (harmless) E. coli in ground chicken meat, and proper refrigeration would prevent UPEC growth. This study can be used by risk assessors and the food industry to decrease the incidence of food-related illness and death from UPEC.
Technical Abstract: Extraintestinal Pathogenic Escherichia coli (ExPEC), including Uropathogenic E. coli (UPEC), are common contaminants in poultry meat, and are a major pathogen associated with inflammatory bowel disease, ulcerative colitis, sepsis, and urinary tract infections. The purpose of this study was to determine the growth potential of UPEC in ground chicken meat. A multi-isolate cocktail of UPEC was inoculated into ground chicken meat 10(3-4) log CFU/g and incubated at 4, 10, 15, 22, and 30 C. The USDA Integrated Pathogen Modeling Program (IPMP) was used to conduct mathematical modeling and validation of UPEC growth using the Huang Primary Model and the Huang Square Root Secondary Model. No growth occurred at 4 C, while the lag phases were ca. 23.6, 11.5, 5.2, and 0.36 h at 10, 15, 22, and 30 C. According to the model, the T-min, the minimum temperature for UPEC growth in ground chicken, was 5.1 C. The growth rates (umax, ln CFU/g h(1) were ca. 0.06, 0.27, 0.48, and 0.90. Approximately 83.9% of the residual errors are between +/- 0.5 log CFU/g, suggesting that the predictive models and the associated kinetic parameters are sufficiently accurate in predicting the growth of UPEC in ground chicken. These models have been validated and can be used in risk assessment of ExPEC in poultry meat.