Assessment of texture and storage conditions of mangoes slices dried by a conductive multi-flash process

Glass transition temperature (Tg) and sorption isotherms can be used to establish state diagrams that help to assess storage conditions to keep the food as an amorphous material in a glassy state. In this study, state diagrams and mechanical properties were assessed to predict the storage conditions of mangoes dried by 1) air-drying; 2) freeze-drying; 3) vacuum-drying and 4) conductive multi-flash drying (KMFD - four cycles of heating/vacuum pulse followed by vacuum-drying). Dried mangoes showed a typical sorption isotherm behavior of hygroscopic materials. In the relative humidity (RH) range investigated (between 11.3% and 90.3%), Tg of processed samples decreased from 44 °C to −68 °C, due to the plasticizing effect of water. Dried mangoes stayed structurally stable at room temperature (25 °C) if storage RH was kept at 25%, in this conditions the moisture content was 0.036 g g −1 (d.b.). The puncture tests results confirmed that, at room temperature, samples stored at RH higher than 30% lost their crispness.