Hot water bath treatments assisted by microwave energy to delay postharvest ripening and decay in strawberries ( Fragaria × ananassa )

BACKGROUND: A lab‐scale approach using microwave (MW)‐assisted hot water treatments was developed and tested to assess the potential of this heating method to delay postharvest ripening and decay in strawberries. Strawberries ( Fragaria × ananassa ) immersed in water were exposed to microwaves at a frequency of 2450 MHz for 3 min at 514 W or 1 min 50 s at 763 W to reach an average temperature of 43.8 ± 0.6 °C at the fruit centre. Another batch was treated in hot water at 45 °C for 15 min, and a final batch was not treated (control). RESULTS: After 9 days of refrigerated storage (3 °C and 90% relative humidity), all heat‐treated strawberries showed significant retention of quality parameters such as colour and firmness and significantly lower yeast and mould populations ( P < 0.05). CONCLUSION: Strawberries subjected to MW‐assisted hot water treatments showed significantly better retention of lightness compared with conventionally treated berries. A short (1 min 50 s) treatment at 763 W was the best choice to prevent strawberry decay. Copyright © 2011 Society of Chemical Industry