45F-1 |
Phytochemical and antioxidant changes in mango (mangifera indica L.) following postharvest and ripening treatments |
A. J. LOUNDS-SINGLETON, D. Del Pozo-Insfran, S. S. Percival, and S. T. Talcott. Dept. of Food Science & Human Nutrition, Univ. of Florida, 359 FSHN Bldg., Newell Dr., PO Box 110370, Gainesville, FL 32611-0370 Mangos (Mangifera indica L.) are an important world fruit crop with market expansion occurring annually in the United States and limited data exists for phytochemicals present in mango and their resultant changes during postharvest handling and ripening. This work investigates ripening associated phytochemical changes in mangos as affected by a postharvest treatment and variable storage temperatures. Unripe mangos (Tommy Atkins) of uniform size were divided and half subjected to a thermal treatment (50°C/60min) for insect disinfestation, and remaining fruit retained as the untreated control. Both groups were further divided in half for storage at 5 and 20°C (air) for 20 days. Fruit held at 5°C were transferred to 20°C after 8 days. Five fruit from each treatment were sampled every 4 days and analyzed in triplicate. L-ascorbic acid (L-AA) and gallic acid (GA) were quantified by HPLC and total soluble phenolics quantified spectrophotometrically as GA equivalents. Antioxidant capacity (AOX) was determined using the oxygen radical absorbance capacity assay. Changes in GA and total soluble phenolics were observed following postharvest treatment and subsequent ripening; however L-AA was unaffected by treatments and increased overall by 40 mg/kg during ripening. The heat treatment decreased initial GA levels, but after storage at 20°C concentrations were equivalent to the control and increased 50 mg/kg during ripening. Fruit initially held at 5°C had decreased GA, indicating ripening inhibition or secondary metabolism. Total soluble phenolics for heat-treated fruit were unaffected by storage temperature and demonstrated a 33 mg/kg increase during ripening. Control fruit storage at 5°C exhibited a 48 mg/kg (30%) decrease in total phenolics, likely resulting from chill injury. AOX was static during ripening with a small increase (2 µmol TE/g) observed for thermally treated fruit stored at 20°C. Heat treatment and decreased storage temperature was generally detrimental to phytochemical concentrations and overall quality of mangos.
Session 45F, Fruit & Vegetable Products: Fruits (Fresh)
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