Reduction of E scherichia coli O157:H7 and S almonella on Fresh-Cut Produce by Caprylic Acid

Abstract

Caprylic acid (CA) was evaluated for reducing Escherichia coli O157:H7 and Salmonella on fresh produce. Spinach, romaine lettuce and iceberg lettuce were inoculated with a cocktail of five E. coli O157:H7 or Salmonella strains, air dried for 30 min and then dipped in CA (10, 25 and 50 ppm) or chlorine (50 ppm) for 60 s. Treated leaves were analyzed for E. coli O157:H7 and Salmonella following treatment and during storage at 4C for 14 days. The CA treatment significantly reduced these pathogens on fresh produce compared to treatment with water (control) and chlorine. E. coli O157:H7 and Salmonella were undetectable in 25 and 50 ppm CA-treated leaves. E. coli O157:H7 and Salmonella were reduced further during storage. The antibacterial activity of CA (5 ppm) was dependent on exposure time. The CA could be used to kill E. coli O157:H7 and Salmonella on fresh produce. Practical Applications Foodborne illness outbreaks associated with fresh produce is a growing concern for the produce industry and regulatory agencies. Effective measures are needed to mitigate the foodborne pathogens at preharvest and postharvest level. Public health concern over the antimicrobial resistance and consumers' preference for chemical- or antibiotic-free food have led researchers to evaluate natural antimicrobials for food safety. We evaluated caprylic acid (CA) as a natural antimicrobial to reduce foodborne pathogens on fresh produce. The results reveal that CA can be used as a produce wash to reduce Escherichia coli O157:H7 and Salmonella on fresh produce.