Proximate Composition and Antioxidant Potential of Moringa oleifera Leaves as Influenced by Different Methods of Preservation

Abstract

Moringa oleifera leaves are recognized as nutritionally and medicinally important for life. Maintaining the freshness of leaves is a challenge due to their very low shelf life. The aim of this study is to examine the effect of the nutritional quality of Moringa oleifera leaves by cost-effective preservation methods. Samples of raw, sundried, oven-dried, and brine-preserved Moringa oleifera leaves were investigated for % proximate compositions based on AOAC methods. The antioxidant potential was analyzed via DPPH assay. The moisture content was significantly (p<0.05) reduced from 40.37±0.08% (fresh) to 27.48±0.20% for Moringa oleifera in brine. Ash content was significantly (p<0.05) reduced from 9.12±0.03% (fresh) to 8.63±0.15% (sun-dried), 8.17±0.08% (oven dried), 7.60±0.08% (in brine). Crude protein content of Moringa oleifera in brine (in bottles) significantly (p<0.05) increased to 26.53±0.06% from 26.50±0.05% (fresh), 24.17±0.13% (sundried), 23.34±0.24% (oven dried). Crude fat content was significantly (p<0.05) reduced from 6.33±0.10% (fresh) to 5.26±0.09% (sun-dried), 4.30±0.15% (oven dried), 3.55 ±0.12% (in brine). Crude fiber content was significantly (p<0.05) reduced from 9.63±0.09% (fresh) to 8.47±0.08% (sun-dried), 8.17±0.03% (oven dried), 6.83±0.14% (in brine). Total carbohydrate content was significantly (p<0.05) increased from 8.20±0.29% (fresh) to 45.90±0.32% (sun-dried), 52.60±0.36% (oven dried), 26.01±0.17% (in brine). The highest antioxidant potential was recorded in Moringa oleifera leaves in brine. (IC50 value is 54.6). Therefore, Moringa oleifera leaves in brine are a product that enhances the quality of nutrients while increasing its shelf life. Sun-dried and oven-dried Moringa oleifera leaf powder is also a cost-effective way of preservation.