Effects of postharvest storage conditions on ‘Tarocco’ orange fruit quality

‘Tarocco Sant’Alfio’ [Citrus sinensis (L.) Osbeck] is a late ripening sweet orange cultivar belonging to the so called “blood oranges”. These fruits are more and more appreciated from consumers for their high nutraceutical value due to the presence of anthocyanins in the flesh. Recently, cold treatment in sweet orange has received more attention due to its usefulness for accomplishing phytosanitary exportation rules, allowing Italian citrus fruit to be sent to Japan and the USA. In addition, cold treatments are useful for increasing pigmentation levels in the fruit. The aim of this work was to define a reliable protocol for postharvest storage of the very-late ‘Tarocco Sant’Alfio’ blood orange to prolong the availability of this product in the market to be used for fresh squeezed orange juice production. Fruits were subjected to three storage treatments (20 days at 1°C plus 50 days at 4°C; 70 days at 4°C; 70 days at 20°C, as control). The results indicate that cold treatments, in particular at 4°C constantly, can extend ‘Tarocco Sant’Alfio’ shelf life and might enhance its qualitative value determining an increase of total anthocyanin content in the flesh. The defined protocols allow prolonging market availability of such a high value product till late June with relevant benefits for the citrus industry and advantages for consumers.