Purpose: This study was undertaken to evaluate consumer cantaloupe preparation strategies on the risk for pathogen contamination and the microbiological shelf life of edible tissue.
Methods: Heavily-netted cantaloupes (n = 12) were inoculated with Salmonella enterica serovar Typhimurium (7.8 log CFU/ml) and Listeria monocytogenes (8.0 log CFU/ml) in buffered peptone water (BPW) and were dried one hour. Uninoculated BPW was used as a negative control on identically-treated cantaloupes (n = 4). Edible tissue was recovered from the cantaloupes by two methods. For the first method, cantaloupes were sectioned into eight parts and the edible tissue removed from the rind and cubed. For the second method, cantaloupes were scored around the circumference with a knife penetrating only to the degree necessary to enable manual separation of the cantaloupe halves. Seeds were removed with a sterile spoon, and edible tissue was scooped without contacting preparation surfaces. Edible tissue was mixed for each cantaloupe, and S. Typhimurium and L. monocytogenes were presumptively enumerated on XLD and MOX agars, respectively, for 25-g samples (n = 18 per cut method over two trials) of cantaloupe tissue. Contamination of contact surfaces was evaluated, and standard plate counts were determined during storage.
Results: Approximately 3 log CFU/g of S. Typhimurium and 4 log CFU/g L. monocytogenes were presumptively recovered from cantaloupe tissue cut by the second method, which were each one log and significantly less than that recovered by the first cut method (P < 0.05). Standard plate counts were also significantly less by two logs at six days of storage for tissue cut by method two. Contamination of contact surfaces was similar for both methods.
Significance: A modified method for cutting cantaloupe can reduce risk of pathogen contamination of edible tissue in spite of high levels of external contamination.