Calcinated calcium killing of Escherichia coli O157:H7, Salmonella, and Listeria monocytogenes on the surface of tomatoes

This study was conducted to evaluate the efficacy of calcinated calcium, 200 ppm chlorine water (1% active chlorine), and sterile distilled water in killing Escherichia coli O157:H7, Salmonella, and Listeria monocytogenes on the surfaces of spot-inoculated tomatoes. Inoculated tomatoes were sprayed with calcinated calcium, chlorinated water, or sterile distilled water (control) and hand rubbed for 30 s. Populations of E. coli O157:H7, Salmonella, and L. monocytogenes in the rinse water and in the residual (0.1% peptone) wash solution were determined. Treatment with 200 ppm chlorine and calcinated calcium resulted in 3.40- and 7.85-log(10) reductions of E. coli O157:H7, respectively, and 2.07- and 7.36-log(10) reductions of Salmonella, respectively. Treatment with 200 ppm chlorine and calcinated calcium reduced L. monocytogenes numbers by 2.27 and 7.59 log(10) CFU per tomato, respectively. The findings of this study suggest that calcinated calcium could be useful in controlling pathogenic microorganisms in fresh produce.