Obtención de “Snacks” de piña (Ananas Comosus) mediante las técnicas combinadas de Ventana de Refractancia y Fritura con Aire Caliente

Abstract

Refractance Window (WR) and Hot Air-Frying (HAF) dried techniques, allows to obtain high nutritional and physicochemical quality fruit snacks. The aim of this work consisted on evaluating WR-AF dry techniques to obtain dehydrated pineapple snacks. MD2 variety pineapple pieces were cut into triangular shapes with 40 mm by side and 4 mm in thickness.
For WR drying, three temperatures were set (70, 80 and 90 °C). For each one, a dry-out kinetics model was applied adopting 4 math models (Newton, Page; Wang & Singh, and Midilli). Also, color as in Luminosity (L*), total color changes (ΔΕ), water activity (aw), diffusion coefficient, and activation energy were determined. On dried samples under WR-HAF mixed method, drying curves were determined, as well as, L*, ΔΕ, aw and vitamin C. In total, four treatments were evaluated in the AF process at 100 °C; three of which were treated samples (TS) under WR, and one sample left untreated (UNTS). Results showed that the higher the drying temperature under WR, the greater the diffusion coefficient and lower the drying time. To reach 9 % (d.b) of humidity, treatments at 90, 80 and 70 °C required 90, 110 and 130 min, respectively. Midilli model adjusted better to drying kinetics. WR-HAF techniques allowed less drying time, higher vitamin C, and color retention compared to UNTS. Results demonstrated that combined WR-HAF is a feasible alternative to obtain pineapple snacks in shorter time while preserving high quality characteristics.