Effect of dehydration methods on quality parameters of drumstick (Moringa oleifera Lam.) leaf powder

A study was undertaken to assess the suitable drying methods for retention of quality parameters of drumstick (Moringa oleifera Lam.) leaf powder. The experiment was laid out in Factorial CRD involving three methods of drying (T-1: Sun drying, T-2: Shade drying and T-3: Cabinet tray dryer) with three pre-treatments (B-1: Unblanched, B-2: Blanched with plain water and B-3: Blanched followed by KMS dip) replicated three times. All the pre-treatments had significant effect on biochemical characteristics of drumstick leaves. Among the pre-treatments, unblanched leaves (B-1) retained higher nutrient contents compared to other pre-treatments. The results of the investigation revealed that among the three different drying methods, shade dried sample was found to retain better nutritional properties. Significantly maximum values for moisture (11.18 %), ascorbic acid (156.27 mg/100g), vitamin-A (22.71 mg/100g), iron (16.54 mg/100g), oxalate (378.66 mg/100g), antioxidant activity (77.11%) and phenol (140.04 mg/100g) were recorded in shade dried sample. The interaction effect between pre-treatment and drying methods showed variation in results. However, the treatment combination T1B1 (Unblanched sun dried) was found to retain high protein (26.43 g/100g), magnesium (318.70 mg/100g) and potassium (1378.79 mg/100g) whereas T2B1 (unblanched shade dried) showed higher ascorbic acid (179.47 mg/100g), saponin (3.66 %), oxalate (541.47 mg/100g) and antioxidant (80.33 %) than rest of the treatment combinations.