Drying kinetics, quality assessment and socio environmental evaluation of solar dried underutilized arid vegetable Cucumis callosus

Abstract

A natural convection solar tunnel dryer of capacity 100 kg was used to analyse the drying kinetics of naturally grown arid vegetable kachri (Cucumis callosus). The moisture reduction was found from 86.10 % to 7.02 % (on wet basis) in two solar days (15 hours). Solar drying curves were estimated using six different drying kinetic models and were compared based on their modeling efficiency. The statistical analysis revealed that Page and Midilli kinetic drying models accurately estimated solar drying characteristics of kachri with a modeling efficiency of 0.971 as compared to other models. Nutritional, microbial, and organoleptic analysis showed that dried kachri product was nutritionally healthy for human consumption. A significant (p<0.01) relationship was found between rehydration characteristics and rehydration time. Techno-economic indicators show that the drying system was economically feasible and could recover investment in 8.70 months. The net carbon dioxide mitigation potential was found 77.05 tons over the lifespan of the dryer.