Ripening associated phytochemical changes in mangos (Mangifera indica) following thermal quarantine and low-temperature storage.
Talcott S. T., Moore J. P., Lounds-Singleton A. J., Percival S. S.
Author Affiliation: Inst. of Food and Agricultural Sciences, Dept. of Food Science and Human Nutrition, Univ. of Florida, P.O. 110370, Gainesville, FL 32611-0370, USA.
Journal of Food Science 70 : C337-C341
Abstract : Fresh mangoes entering the USA must be subjected to a thermal quarantine treatment to eliminate invasive pests, commonly followed by cold storage to extend shelf life. Changes in phytochemicals and their resultant antioxidant capacity after such treatments are unknown. These studies evaluated mature, green mangoes subjected to a simulated quarantine treatment using hot water immersion at 50°C for 60 minutes and subsequent storage at 5 and 20°C against their respective controls. Fruits held at 5°C were transferred to 20°C after 8 days of storage to complete ripening, whereby symptoms of chill injury were observed. Phytochemical, antioxidant capacity and quality parameters were then assessed every 4 days as the fruit ripened over the next 20 days. Storage temperature during ripening and not the hot water treatment was the major factor contributing to changes in polyphenolic content, with antioxidant capacity unaffected by either postharvest treatments or ripening. Major polyphenolics identified were free gallic acid and 4 gallotannins that collectively increased in concentration by 34% as the fruit ripened, also independent of postharvest and storage treatments. Carotenoid concentrations were highest in hot water-treated fruits stored at 20°C, whereas storage at 5°C initially delayed ripening. Despite appreciable differences in fruit quality during quarantine treatment or low temperature storage, only minor differences in antioxidant phytochemicals were observed.