EFFECTS OF UV-C ON BIOACTIVE COMPOUNDS AND QUALITY CHANGES DURING SHELF LIFE OF SWEET CHERRY GROWN UNDER CONVENTIONAL OR REGULATED DEFICIT IRRIGATION

摘要

The effect of a UV-C postharvest treatment (4 kJ m(-2)) on physicochemical quality, phenolic contents and total antioxidant capacity of 'Prime Giant' sweet cherry throughout 20 d at 2 degrees C (simulated cold storage during transportation period) plus 5 d at 15 degrees C (additional shelf life period) was studied. Furthermore, the effect of two regulated deficit irrigation strategies, with 36-39 % water savings, was also studied on such quality parameters. In general, physicochemical quality at harvest (soluble solids content 16-18 %; titratable acidity: 11.2-12.4 g L-1) was unaffected throughout the storage periods, independently on storage time, regulated deficit irrigation or postharvest treatments. As observed from the darker red colour, cherry skin showed approximate to 9-10-fold higher phe- nolic contents and total antioxidant capacity than cherry flesh. Cyanidin-3-rutinoside was the major anthocyanin. Generally, phenolic compounds of cherry skin decreased during storage. However, UV-C treatment lowered such reductions, even increasing total phenolic content by 21-36 % after shelf life in fruit grown under regulated deficit irrigation. Conclusively, a UV-C pre-treatment can be considered as an excellent postharvest tool to increase sweet cherry phenolic compounds. Furthermore, a UV-C pre-treatment can be even combined with regulated deficit irrigation strategies to reduce natural resources consumption without affecting fruit quality, which is particularly interesting in Regions with scarce water availability.