Chemical Characterization and Antioxidant Capacity of Flour from Two Soya Bean Cultivars (Glycine Max)

Abstract

A comparative study was conducted to evaluate the chemical composition and antioxidant capacity of flour derived from two soybean (Glycine max) cultivars: one local variety (Oued Smar, Algeria) and one imported Chinese variety. The chemical composition, including ash, protein, and fat content, was analyzed. Potassium (K⁺) and sodium (Na⁺) were quantified using a flame photometer. Additionally, polyphenol content and antioxidant activity (FRAP assay) of methanolic extracts from the flours were assessed. The results revealed that the soybean flours contained approximately 8% moisture, over 50% protein, 1.58–1.87 g of fat, and 0.28–0.30 g of ash. Minor differences in mineral content were observed, with potassium levels reaching 489 mg/mL and sodium levels at 20 mg/mL. The total phenolic content of methanolic extracts was around 37 mg GAE/g in both flours. The antioxidant potential (FRAP) of the Chinese variety was slightly higher, likely due to its polyphenol richness. Both soybean flours demonstrated significant protein and phenolic content, with notable antioxidant properties, underscoring their value as functional food ingredients.