Frontiers in Sustainable Food Systems (Dec 2018)
Reducing Transfer of Salmonella and Aerobic Mesophilic Bacteria on Melon Rinds Surfaces to Fresh Juice by Washing With Chlorine: Effect of Waiting Period Before Refrigeration of Prepared Juice
Abstract
Cantaloupes, honeydew melons and watermelons inoculated with Salmonella cocktail at 4.5, 3.8, and 3.2 log10 CFU/cm2, respectively, were sanitized with 200 ppm chlorine before rinds removal, cutting, and juice preparation. Efficacy of 200 ppm chlorine in reducing transfer of Salmonella, aerobic mesophilic bacteria, yeast and mold, and Pseudomonas from the melon surfaces to freshly prepared fruit juice was investigated including the effect of waiting period before refrigeration of the juices. The melon juice filtrates were refrigerated immediately or stored at room temperature (~22°C) for 3 and 5 h before refrigeration. Average Salmonella bacteria recovered in fresh melon juice prepared from unwashed whole cantaloupes, watermelon and honeydew melons was 1.4, 0.5, and 0.4 log10 CFU/ml, respectively. Juices from unwashed inoculated melons had the highest bacterial populations and storage at an abusive temperature of 10°C led to proliferation. Holding these juices at room temperature for 5 h before refrigeration allowed Salmonella bacteria to increase by 0.5–0.8 log in cantaloupe juice and 0.3–0.5 log in watermelon and honeydew juices. No Salmonella bacteria was determined in fresh juices prepared from melons washed with chlorinated water. The results of this study showed that washing melons with 200 ppm chlorine before juice preparation and immediately refrigerating the juice will minimize the chances of Salmonella proliferation.
Keywords