Effect by using a modified solar dryer on physicochemical properties of carambola fruit (Averrhoa carambola L.)

Abstract

Carambola is an excellent C-vitamin source and other healthy nutrients; unfortunately, because its high moisture content is a S.A. Medina-Moreno, S. Huerta-Ochoa, C.A. Lucho-Constantino, L. Aguilera-Vázquez, A. Jiménez-very perishable fruit. Solar drying is a feasible solution for its preservation. However, the optimal drying conditions depend on González y M. Gutiérrez-Rojas the dryer material. A natural convection sun-dryer was modified using four different materials: glass, acrylic, polycarbonate, and polyethylene. The moisture259 Crecimiento,content of sobrevivenciacarambola slicesy adaptaciónwas reducedde Bifidobacteriumfrom 89.23%infantisto finala condicionesmoisture contentácidas between 2.2% and 5.9% in a maximum time of (Growth, 650 min. survival The and final adaptation water activity of Bifidobacterium of dried samples infantis ranged to acidic from conditions) 0.310 to 0.414. The color analysis of carambola indicated a decrease in lightness while a and b parameters increased; the mix of red and yellow resulted in an L. Mayorga-Reyes, P. Bustamante-Camilo, A. Gutiérrez-Nava, E. Barranco-Florido y A. Azaola-orange product which turned slightly brown as lightness decreased. In addition, the ascorbic acid reduced from 338.46 mg/100 g (d.b) to 159.50 mg/100 Espinosa g-124.37 mg/100 g (d.b), depending on the cover material. In general, polycarbonate dryers show less degradation of components265 Statisticaldueapproachto the lowerto optimizationtemperaturesof reachedethanol fermentationin their dryingby Saccharomyceschamber. However,cerevisiaethe solarin thedrying of carambola with all the covers is technically, economically, and environmentally feasible compared to conventional technologies, presence of Valfor® zeolite NaA such as the electric oven used in this work.