Submitted to: Journal of Food Protection
Publication Type: Peer reviewed journal
Publication Acceptance Date: 11/6/2005
Publication Date: 4/1/2006
Citation: Fan, X., Annous, B.A., Sokorai, K.J., Burke, A.M., Mattheis, J.P. 2006. Combination of hot water surface pasteurization of whole fruit and low dose gamma irradiation of fresh-cut cantaloupe. Journal of Food Protection. 69(4):912-919. Interpretive Summary: Fresh-cut cantaloupe, either as a single component product or as one part of a multi-component fruit salad, is available year around in the United States. However, consumption of cantaloupe has been linked to a number of outbreaks and deaths in the U. S. due to contamination with foodborne pathogens. During cutting and processing, pathogens on the surface of whole fruit may be transferred onto fresh-cut pieces, the final product. Food safety intervention technologies are needed for both whole and cut melons. In this study, we treated whole melon fruits with hot water followed by low dose irradiation of cut fruit after packaging. Our results showed that hot water surface pasteurization of whole cantaloupe combined with low dose irradiation of the fresh-cut product provided greater microbial reduction than either treatment alone. The combination of the two treatments had little effect on quality of fresh-cut cantaloupe. A combination of hot water pasteurization of whole fruit with low irradiation of cut cubes can be used to reduce the microbial population and extend the shelf life of fresh-cut cantaloupe. The information should provide the fresh-cut industry a means to enhance safety and quality of cut melons.
Technical Abstract: Improvements in methods for disinfecting fresh-cut cantaloupe could reduce spoilage losses and reduce the risk of food-borne illness from human pathogen contamination. The objective of this study was to investigate the feasibility of using hot water treatment in combination with low dose irradiation to reduce native microbial populations while maintaining the quality of fresh-cut cantaloupe. Whole cantaloupes were washed in tap water at 20 or 76 C for 3 min. Fresh-cut cantaloupe cubes, prepared from the washed fruit were then packaged in clamshell containers, and half the samples were exposed to 0.5 kilogray of gamma radiation. Native population of microflora and sensory qualities were determined during subsequent storage at 4 C over a period of 7 days. Results showed that hot water surface pasteurization reduced the microflora population by 3.3-logs on the surface of whole fruits, resulting in a lower microbial load on fresh-cut cubes, compared to those from cold water treated fruit. Irradiation of cubes prepared from untreated fruit to an absorbed dose of 0.5 kilogray achieved similar low microbial load of the cubes as those prepared from hot water treated fruit. The combination of the two treatments further reduced the microflora population. During storage, the headspace atmosphere of the packages was not significantly influenced by any of the treatments. Color, titratable acidity, pH, ascorbic acid, firmness, and drip loss were not consistently affected by treatment with irradiation, hot water or the combination of the two. Cubes prepared from hot water treated whole fruit had slightly lower soluble solids content. Our results showed that the combination of hot water pasteurization of whole cantaloupe and low dose irradiation of packaged fresh-cut melon can reduce the population of native microflora while maintaining quality of this product.