Survival of Foodborne Pathogens in Homemade Fig and Mulberry Vinegars

Abstract

This work reports the survival status of Listeria monocytogenes, Escherichia coli O157:H7, Staphylococcus aureus and Salmonella Typhimurium in homemade fig and mulberry vinegar. Each pathogen was separately inoculated in vinegar samples at approximately 7 log CFU/mL. The survival status of pathogens was examined at 20°C for 0, 15, 30 and 60 min, and 4, 8 and 24 h. The residual populations after 24 h were below detection limit for all species assayed. S. Typhimurium was much more sensitive to mulberry vinegar ( 6 log reduction in 30 min) than it is to fig vinegar ( 6 log reduction in 24 h). L. monocytogenes had an overall quite different behaviour, being the most sensitive species to fig vinegar ( 6 log reduction in 4 h) while being the most resistant one to mulberry vinegar ( 6 log reduction in 24 h). The total phenolic content of fig vinegar (767 mg GAE/L) was higher than mulberry vinegar (557.5 mg GAE/L). The results exhibited that antimicrobial activity of vinegar is mainly related to the contact time, test pathogen and physicochemical properties of vinegar.

Keywords

• homemade vinegar
• fig
• mulberry
• survival
• foodborne pathogens