Resumen
The present work was carried out to evaluate the application of delayed ripening (employing controlled atmosphere (CA) storage) to minimize or alleviate the development of the ripening disorder known as internal bruising. Tomato (Lycopersicon esculentum Mill.) fruits, cv. Solimar, were harvested in Bradenton (Florida) at the mature-green stage and gassed with 100 mL•L-1 of ethylene at 20oC to screen out immature-harvested fruits. Breaker stage tomatoes were either dropped from a 40-cm height to induce internal bruising or not dropped. Half of the two treatments was stored in CA (3% O2; 4% CO2; balance N2) for 8 days at 20 C and 85-95% relative humidity, then transferred to air until completely ripe. The other tomatoes were stored continuously in air at the same temperature and RH. At the ripe stage, dropped tomatoes from CA or continuous air treatments exhibited visible symptoms of internal bruising in locule tissues. Storage atmosphere did not cause significant differences in vitamin C, or total carotenoids for bruised locule or pericarp tissues. However, bruised locule tissue from CA storage had titratable acidity 15% higher (about 162 meq citric acid•kg-1) than tissue from air storage (about 140 meq citric acid•kg-1), and was similar to air-stored, unbruised locule tissue (about 174 meq citric acid•kg-1). Pericarp tissue was also analyzed for electrolyte leakage (EL) and polygalacturonase (PG) activity. Pericarp tissue from the impacted region had similar PG activity for CA or air treatments (705 and 710 (µmol GA•kg-1 h-1 respectively). EL of bruised, pericarp tis sue was similar for CA and air storage (about 50%) and about 40% for unbruised tissues from either storage treatment. Internal bruising can be minimized only by reducing the number and intensity of drops during harvest and handling operations.
