EFFECTS OF DIFFERENT DRYING METHODS ON THE NUTRITIONAL, BIOACTIVE, AND SENSORY QUALITIES OF CORIANDER LEAVES

Abstract

Coriander leaves, valued in culinary, medicinal, and cosmetic fields, degrade quickly post harvest senescence resulting in large losses. So, this study examined sun drying (SD), cabinet drying (CD), microwave drying (MD), and freeze drying (FD) to determine their impact on the physicochemical and bioactive properties of coriander leaves and their use in vegetable soup. According to the results, FD had the highest lightness (L* value) at 34.92, while MD had the lowest (16.17). Except for MD, every method successfully kept the green color with negative a* values. CD had a high chroma (20.17) and a low total color change (2.32), whereas MD showed the opposite. MD lost the most weight (88.27%) while having the quickest drying time (1.28 hours). The results indicate that the SD samples had the highest total phenolic content (TPC) of 120.26 µg GAE/g DM, total flavonoid content (TFC) of 64.33 µQE/g DM, and antioxidant activity (2.30 µM TE/g DM), with CD, MD, and FD following closely after. The CD had the strongest anti-diabetic effects. The levels of chlorophyll retention were lowest in MD and highest in CD in the aspect of chlorophyll b (22.15 µg/ml) and total chlorophyll (34.68 µg/ml). The CD is the best method for drying coriander leaves, preserving bioactive ingredients, physicochemical characteristics, and sensory appeal. CD samples outperformed others in taste, aroma, and overall quality, especially in vegetable soups, making the CD a cost-effective, efficient, and high-quality drying method compared to SD, MD, and FD.