Drying of onion shreds in corrugated electric and solar-conduction dryers: Techno-economic evaluation and quality degradation kinetics

Abstract

Drying of onion shreds in solar conductive dryer (SCD) and corrugated electrical solar conductive dryer (CESCD) are explored in this study. An attempt to improve the sample loading volume of SCD and CESCD is made using a fixed bed dryer (FBD) for initial drying. The techno-economic analysis is carried out for different pattern loading on SCD and CESCD. The techno-economic aspects analyzed include efficiency of dryer, payback period, life cycle savings, and internal rate of returns (IRR). Drying characteristics—drying rate, moisture ratio, and temperature profile of both dryers were compared. CESCD showed higher drying rate and IRR than SCD. Data fitted best in Page model. In terms of energy requirement, the overall drying efficiency of SCD was better than CESCD. Patterns 1 and 3 retained the color better, but were not cost-effective and profitable. Flavor and bioactives were higher in SCD than CESCD dried onion shreds.