Effect of different postharvest hot water treatments on quality and storability of 'marsh' grapefruit

Different postharvest combinations of hot water temperatures and treatment times were used on 'Marsh' grapefruit to determine their effects-on quality and storability of the fruit at 4 degrees C. Water immersion of fruit at constant 48 degrees C for 2 or 3 hrs significantly increased weight loss, soluble solids content, pH, decay (> 30 %), and reduced % juice, titratable acidity, firmness, and color intensity after 90 days of storage at 4 degrees C. No loss in quality resulted from postharvest immersion of the fruit at constant 45 degrees C for 3 hrs. Weight, firmness, and natural color were retained. No chilling injury or decay symptoms were detected after 90 days storage at 4 degrees C in fruit treated with 45 degrees C water for 3 hrs. Control fruit developed > 35 % chilling injury after storage at 4 degrees C for 90 days. Hot water immersion at constant 45 degrees C for 3 hrs was the best treatment for grapefruit quarantine. Shelf-life of grapefruit can be prolonged and fruit quality can be maintained at low storage temperature (4 degrees C) when the fruit were treated with 45 degrees C for 3 hrs after harvesting.