Purpose: The objective is to evaluate the antimicrobial efficacy of potassium cinnamate against L. monocytogenes in dairy dessert and Z. bailii in tomato sauce.
Methods: L. monocytogenes was inoculated to have ca. 2-3 log CFU/ml counts in the dairy dessert with pH of 6.38, and aw of 0.992. Treatments with potassium cinnamate (PuraQTM Xtend AX66) with 0, 0.10, 0.20, and 0.30% concentrations were prepared. The L. monocytogenes inoculated samples were stored at 4 °C for analyses throughout the incubation period. Z. bailii was inoculated to have ca. 2-3 log CFU/ml counts in the tomato sauce with pH of 3.87, and aw of 0.940, respectively. Treatments with potassium cinnamate (PuraQTM Xtend AX66) with 0, 0.02, 0.06, and 0.10% concentrations were prepared. The Z. bailii inoculated samples were stored at 12 °C for analyses throughout the incubation period. The plating for each microorganism was done independently at ca. 0, 3, 7, 14, 21, and 42 days.
Results: The L. monocytogenes growth data in the dairy dessert indicate that at minimum use level of 0.1%, potassium cinnamate arrested the growth of the pathogen to the inoculation levels over the incubation period. The tomato sauce study for Z. bailii indicate that at 0.02% use level, potassium cinnamate controlled the growth for 14 days and at 0.06% concentration levels, the growth of Z. bailii was inhibited over the incubation period.
Significance: This research substantiates the excellent antimicrobial efficacy of potassium cinnamate against pathogenic and spoilage microorganisms at very low levels in dairy dessert and tomato sauce. This research provides food industry with a highly effective antimicrobial to assure the food safety as well as to extend the shelf-life of food products.