Effect of storage temperature on survival and growth of foodborne pathogens on whole, damaged, and internally inoculated jalapeños (Capsicum annuum var. annuum).

Abstract

There is a lack of general knowledge regarding the behavior of foodborne pathogenic bacteria associated with jalapeño peppers. The survival and growth behaviors of Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella enterica on the interior and exterior of jalapeño peppers were determined under different storage conditions. Jalapeños were inoculated with a five-strain cocktail of L. monocytogenes, E. coli O157:H7, or S. enterica on the intact external surface, injured external surface, or intact internal cavity of jalapeño peppers and held at 7 or 12°C for a period of 14 days. Populations of each pathogen were determined at 0, 1, 2, 5, 7 10, and 14 days throughout storage. The uninjured, intact external surface of jalapeño peppers did not support growth of the pathogens tested under both storage conditions, with the exception of L. monocytogenes at 12°C. Populations of E. coli and S. enterica declined on the external injured surface of peppers at 7°C, but populations of L. monocytogenes remained consistent throughout the length of storage. At 12°C, L. monocytogenes and S. enterica populations increased throughout storage, and E. coli populations remained unchanged on injured surfaces. The uninjured internal cavity of the jalapeño supported growth of all pathogens at 12°C. Overall, L. monocytogenes was the microorganism most capable of growth and survival in association with jalapeño peppers for the scenarios tested. Results emphasize the importance of jalapeño pepper quality and proper storage conditions in preventing or reducing pathogen survival and growth.