Influence of Blanching and Drying Methods on the Retention of Nutritional Quality of Dried Moringa Leaves

The research work on “Influence of blanching and drying methods on the retention of quality of dried Moringa (Moringa oleifera Lam.) leaves” was conducted at Horticultural College and Research Institute for Women, Tiruchirappalli, Tamil Nadu. Moringa leaves need to be used on the same day of harvesting due to shorter shelf life and leaf yellowing and suitable processing technique is essential to extend the shelf life. Water blanching of leaves was done at 50^o, 60^o, 70^o and 80^oC for 1, 2 and 3 minutes. Among twelve blanching methods, water blanching at 50^oC for 3 minutes was found to be the best in retention of total carotenoids, vitamin C, iron and calcium and less non-enzymatic browning in dehydrated moringa leaves. Sensory quality was recorded highest in water-blanched, dehydrated moringa leaves stored in HDPE and LDPE bags. After water blanching at 50^oC for 3 minutes, the moringa leaves were dried in sun drying, shade drying and cabinet drying. Among drying methods, the drying ratio was found to be highest in cabinet-dried moringa leaves in water blanching as pre-treatment. Cabinet-dried moringa leaves after water blanching at 50^oC for 3 minutes retained the highest total carotenoids (124.65 mg/100g), vitamin C (467.25 mg/100g), iron (21.50 mg/100g) and calcium (1413.10 mg/100g) content. Cabinet drying of moringa leaves after water blanching recorded the least non-enzymatic browning (1.03 O.D.). The sensory quality was found to be highest in cabinet-dried moringa leaves (8.8).