Drying rate of three types of solar dryers in golden berry (Physalis peruviana L.)

Abstract

In this research, the objective was to determine the drying rate of aguaymanto (Physalis Peruviana L.) in three different solar dryers. To accomplish this aim three prototypes were designed and built direct, indirect, and mixed dryer. The drying process went through solar radiation and natural hot air convection generated by solar collectors. During rehearsals, weather conditions were recorded: average wind speed of 1.11 m/s, the relative air humidity (RH) ranged from 16% to 52%, and the minimum and maximum ambient temperature were 14.7 ºC (287.8 K) and 26.4 ºC (299.5 K). The initial moisture (bs) was 4.53 and the final moisture of 0.07; 0.12 and 0.10 (kg water/kg dry solid), respectively. Drying rates reached values: 0.0287; 0.0208 and 0.0407 (kg water/hour·m2). Drying time: 41 h for direct type, 56 h for indirect 56 h, and 29 h mixed. Solar drying is a viable, natural, economical, and easy alternative to use for food de-hydration.