Nutritional, phytochemical composition, and antioxidant activity of Moringa oleifera leaf powder decolorized under optimized conditions

The use of Moringa oleifera leaves in foods is limited due to the green coloration that negatively impacts consumer acceptability. Moringa oleifera leaf powder (MOLP) was decolorized under optimized conditions of extraction time (10–30 min), solute to solvent ratio (1:20 to 1:5 w/v), and solvent concentration (50–95% v/v) using Box–Behnken design (Response Surface Methodology). Selected color parameters, nutrient, phytochemical content, and antioxidant properties were response variables. Protein content (31.75% w/w) and the antioxidant activity (2-diphenyl−1-picrylhydrazyl [DPPH]: 83.04% w/w) of decolorized MOLP were significantly (p ≤ .05) higher than those of the undecolorized MOLP (protein 28.94% w/w:DPPH:73.52%). The mineral composition (potassium, magnesium, phosphorus, zinc, and manganese) of the decolorized samples also increased significantly (p ≤ .05), whereas phytate and tannin content decreased significantly (p ≤ .05) under optimized conditions. Decolorization under the reported optimized conditions is a promising alternative to enhance the use of MOLP in food enrichment/fortification. Novelty impact statement The present study has demonstrated that decolorization of MOLP under optimum conditions of extraction time (10–30 min), solute to solvent ratio (1:20 to 1:5 w/v), and solvent concentration (50–95% v/v) has the potential to improve the consumer acceptability of foods enriched with MOLP. This process could also allow for the addition of higher levels of MOLP in foods thus, increasing the overall nutrient intake and improving the health of consumers.