Effect of drying methods and storage on bioactive compounds of Moringa oliefera leaf powder

Moringa oleifera (Drumstick tree) is well known for its nutritional quality but usage of leaf powder as a functional ingredient is very less. Hence, the leaves were subjected to hot-air, solar-tunnel and shade drying methods and stored under ambient condition. Solar tunnel drying had 89.58 and 16.66% lesser drying time compared to shade and hot-air drying, respectively. The study showed that solar-tunnel dried leaf powder had high ascorbic acid (471 mg /100g), total carotenoids (2.49 mg/g), total polyphenols (39.29 mg gallic acid equivalent /g) and total chlorophyll (7 mg/g) content compared to other drying methods. Higher retention of bioactive compounds was found in solar-tunnel dried leaf powder during storage. Aerobic plate count was higher in shade dried sample throughout the storage period. It can be concluded from the study that solar-tunnel drying is the best green technology to obtain moringa leaf powder with high retention of bioactive compounds which can be utilized as a functional ingredient in food preparations.