Prestorage hot water treatments (immersion, rinsing and brushing)

This review summarizes the latest developments in hot water immersion treatment (HWT) and hot water rinsing and brushing (HWRB) technologies. These treatments kill pathogens that cause surface decay, while maintaining fruit quality during prolonged storage and marketing. They also are relatively easy to use, have a short operating time, and are efficient in heat transfer. The cost of a typical hot water technology commercial system is significantly less than that of a commercial vapor heat treatment system. The physiological responses of cultivars of different fruit species to heat treatments vary according to season, growing location, soil type, production practices and fruit maturity. In general, the higher the temperature, the shorter the treatment in order to avoid heat damage. HWT is applied at temperatures between 43 and 53 degreesC for periods of several minutes up to 2 h for quarantine treatments, while HWRB is employed commercially for 10-25 s at temperatures between 48 and 63 degreesC. The time and temperature of exposure that benefits fresh harvested quality depends on cultivar, fruit maturity, fruit size and condition during the growing season. Both HWT and HWRB inhibit ripening, reducing decay incidence and in several commodities induce resistance against pathogens and against chilling injuries. (C) 2003 Elsevier B.V. All rights reserved.