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

Carambola is an excellent C-vitamin source and other healthy nutrients; unfortunately, because its high moisture content a very perishable fruit. Solar drying feasible solution for preservation. However, the optimal conditions depend on dryer material. A natural convection sun-dryer was modified using four different materials: glass, acrylic, polycarbonate, polyethylene. The of carambola slices reduced from 89.23% to final between 2.2% 5.9% in maximum time 650 min. water activity dried samples ranged 0.310 0.414. color analysis indicated decrease lightness while b parameters increased; mix red yellow resulted orange product which turned slightly brown as decreased. In addition, ascorbic acid 338.46 mg/100 g (d.b) 159.50 g- 124.37 (d.b), depending cover general, polycarbonate dryers show less degradation components due lower temperatures reached their chamber. solar with all covers technically, economically, environmentally compared conventional technologies, such electric oven used this work.