Purpose: Our objective was to develop a commercial-scale surface pasteurization process for enhancing the microbiological safety of cantaloupes.
Methods: Whole cantaloupes, surface inoculated with S. Poona RM 2350, using the dip method, were stored at 32°C for 24 h prior to processing to allow for strong attachment and biofilm formation. Inoculated cantaloupes were treated in 275 l of hot water at 92°C for 60 and 90 s.
Results: Hot water treatments at 92°C for 60 and 90 s have resulted in excess of 5 log reduction of S. Poona per g cantaloupe rind. Cantaloupes that were treated and stored at 4°C for 9 days retained their firmness qualities and maintained non-detectable levels of S. Poona as compared to the controls. Also, levels of S. Poona on fresh-cut cantaloupes prepared from treated cantaloupes and stored for 9 days at 4°C were non-detectable as compared to the controls. Temperature penetration profiles indicated that the surface temperature of the whole cantaloupe was 26-30°C below the wash water temperature.
Significance: These results indicate that surface pasteurization at 92°C for 90 s will enhance the microbiological safety of cantaloupes and will extend the shelf life of this commodity as well. This process parameters, short time treatment of 90 s or less, fall within the commercial requirements of the whole cantaloupe processors/packers industry.