EFFECT OF POSTHARVEST SHORT HOT-WATER RINSING AND BRUSHING TREATMENT ON DECAY AND QUALITY OF STRAWBERRY FRUIT

Strawberry (Fragaria ananassa) cv. "Feng xiang" was treated with hot water rinsing and brushing (HWRB) at 20C (control), 55C (HWRB-55), 60C (HWRB-60) and 65C (HWRB-65) for 20 s. The effect of these heat treatments on fruit decay and quality was investigated after either ambient temperature storage (20C) for 3 days or cold storage (0C) for 12 days. Results showed that HWRB treatments could significantly reduce the epiphytic microbial population on fruit surface, decay development and weight loss. Fruits treated with HWRB-65 had the lowest decay incidence and decay index, but about 60% of the treated fruits showed heat damage and became commercially unacceptable. Fruits treated with HWRB-60 showed less decay than the control fruits, and cold storage could enhance the effect of HWRB treatments. There were no negative effects of HWRB-60 on fruit surface color, firmness, soluble solids content and titratable acidity. PRACTICAL APPLICATIONS This research investigated the effects of hot water rinsing and brushing (HWRB) treatments on decay and quality of strawberry fruit, which was susceptive of decay. HWRB treatments at 60C for 20 s significantly reduced fruit decay, did not affect its quality and could be suggested as a potential postharvest heat treatment on strawberry fruit. On a commercial scale, this short HWRB treatment would be a desirable method for treating freshly harvested produce to maintain fruit quality during postharvest period. Future work on exploring HWRB technology to a broader range of freshly harvested commodities with improved fruit quality and meeting the quarantine requirements, will help the fruit industry to develop environmentally friendly and technically effective HWRB technologies, and possibly reduce the current extensive reliance on chemical pesticides.