30B-19 |
Evolution of sugars in Manila mangoes after hydrothermal treatment and chilling stress |
H. S. GARCIA1, A. Velazco, K. P. Rodriguez, S. Zarate, and J. De la Cruz. (1) UNIDA, Instituto Tecnologico de Veracruz, M.A. de Quevedo # 2779, Col. Formando Hogar, Veracruz, Ver., 91897, Mexico Chilling injury is a physiological disorder that has been studied in tropical fruits as mangoes. Among the most severe symptoms abnormal ripening involving carbohydrate metabolism has been reported. Starch breakdown and sugar synthesis are at least partly responsible for quality and acceptability of the fruit. Additionally, hydrothermal treatments have to be applied to mangoes destined for export markets. Our objective was to evaluate changes in the main sugars in Manila mangoes that were hydrothermaly treated and then stored under refrigeration. Manila mangoes were obtained from the local market in mature-green stage, and immersed in water at 46.1 °C for 65 min. Control (no heat-treated) and treated fruits were stored at 6, 12 or 25 °C. Samples were withdrawn every 5 days for refrigerated and every 2 days for ripening mangoes. Analyses performed were weight loss, textural firmness, color, soluble solids, pH, acidity, total reducing sugars, and individual sugars by HPLC. Variable trends were observed during storage and ripening in control and treated fruits for the typical compositional variables. Differences were noted in glucose content of mangoes stored at different temperatures and treatments. Overall, the trend was to find control mangoes with more elevated sucrose content than heat-treated mangoes. In turn, glucose was higher while fructose was lower in control as compared to treated mangoes. Hydrothermal treatment had an effect on sugar metabolism in mangoes. This needs to be studied as for the possible impact on the sensory quality of the product.
Session 30B, Fruit & Vegetable Products: Sensory, Product Development, Fresh-Cut, and Storage
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