Sustainable solar assisted drying of chickpea (Cicer arietinum L.): a comparative study on energy use, rehydration and sensory attributes

Drying chickpeas to produce ready to reconstitute products offers a sustainable approach to improving their convenience and utilization. However, drying is energy-intensive, and optimization is essential for both efficiency and product quality. This study investigated the drying kinetics, energy efficiency, rehydration behavior, and sensory attributes of soaked and cooked chickpeas using a solar-assisted forced convection system under varying air temperatures (50–80 °C) and airflow rates (118.02–478.54 kg/h). Results showed that soaked chickpeas dried faster (4.0–17.5 h) and required less energy than cooked chickpeas (6–21 h), with solar energy contributing up to 50% of the total requirement under favorable conditions. Specific energy consumption increased with airflow rate but declined at higher drying temperatures, indicating that optimal performance occurred at elevated temperature and reduced airflow. Rehydration studies revealed that cooked chickpeas achieved slightly higher rehydration ratios and moisture regain due to structural modifications during cooking, while soaked chickpeas demonstrated satisfactory reconstitution ability with lower energy demand. Sensory evaluation indicated that moderate drying conditions (50–60 °C, 0.50–0.75 m/s airflow) yielded the most acceptable products. Soaked chickpeas were preferred for color and taste, while cooked chickpeas scored better in texture and overall mouthfeel. Overall, solar-assisted drying proved effective for producing energy-efficient, rehydratable chickpea products with desirable sensory quality. The results suggest that soaked chickpeas are more suitable for energy-optimized processing, whereas cooked chickpeas may be preferred when superior rehydration and textural properties are required.