Effects of Opuntia ficus indica extracts on inactivation of Escherichia coli O157:H7 and Listeria monocytogenes on fresh-cut apples

We investigated the antibacterial effects of Opuntia ficus indicaextracts on foodborne pathogens, Escherichia coliO157:H7 and Listeria monocytogenes, on the medium of sliced apples. Pathogens were inoculated on sliced apples and immersed for 10 min in Opuntia ficus indica extracts. Each sample was packaged and stored at 4°C and 21°C for 8 days. The populations of E. coliO157:H7 and L. monocytogenessignificantly decreased with increasing extract concentration (p<0.05). In particular, L. monocytogeneswas reduced to non-detectable levels after 2 days in 50 mg/mL treatment at 4°C and 21°C Opuntia ficus indicaextracts therefore have antibacterial effects on the two foodborne pathogens. Sensory evaluation results indicated that treated apples had better sensory characteristics than did the control. Therefore, the results suggest that Opuntia ficus indicaextracts could be useful as a natural food preservative to improve microbial safety.