Title: Survival and growth populations of Salmonella transferred from melon rind surfaces to cantaloupe, honeydew, and watermelon pulps during preparation Author
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: July 28, 2013
Publication Date: July 28, 2013
Citation: Ukuku, D.O. 2013. Survival and growth populations of Salmonella transferred from melon rind surfaces to cantaloupe, honeydew, and watermelon pulps during preparation. Meeting Abstract. Annual IAFP meeting., Charlotte, NC., July 28-31, 2013. Volume 1, Page 1. Technical Abstract: Consumers are eating more fresh vegetable and fruit due to nutritional and health-related benefits. Whole melons (cantaloupes, honeydew and watermelons) are of particular interest because of their nutrient contents. However, they are frequently contaminated with foodborne pathogens. Conditions necessary for survival and growth of transferred Salmonella spp. and aerobic mesophilic bacteria from melon rind surfaces to pulps during preparation were investigated. Fresh-cut pieces prepared from whole cantaloupes, honeydew and watermelons inoculated with a Salmonella cocktail at 6.2 log CFU/cm2 and washed with chlorinated (200 ppm) water were blended using a waring commercial blender, speed set at level 5 for 1 min. to generate melon purees. Some of the purees were refrigerated immediately at 5 deg C or 10 deg C while others were left at room temperature (~22 deg C) for 3 h before refrigeration. Aerobic mesophilic bacteria determined in the purees averaged 3.3 log CFU/g for cantaloupe, 2.3 log CFU/g for honeydew and 1.5 log CFU/g for watermelon, while populations of Salmonella spp. in cantaloupe pulp was 1.5 log CFU/g, and less than 1.0 log CFU/g in honeydew and watermelon purees. All microbial populations did not change in melon purees stored immediately at 5 deg C for 12 days with the exception of aerobic mesophilic bacteria. However, Salmonella populations in melon purees stored at 10 deg C for 12 days increased slightly but were not significantly different from the initial populations. Populations of Salmonella spp. in cantaloupe, honeydew and watermelon purees left at room temperature (22 deg C) for 3 h before refrigeration increased by 0.6 log, 0.3 log, and 0.4 log respectively, and were higher than the populations determined at 5 deg C or 10 deg C for the same number of hours. The results of this study show that holding freshly prepared contaminated melon purees at 22 deg C for 3 h or more prior to refrigeration would increase the risk of Salmonella proliferation.