Physicochemical and functional properties of a protein-rich fraction produced by dry fractionation of chia seeds (Salvia hispanica L.)

Abstract

Due to possible denaturation, the protein extraction method has a major impact on its functional properties in food. Dry milling and fractionation produce less protein modification and require no effluents. The physicochemical and functional properties were evaluated for Salvia hispanica L. seed protein-rich fraction (SPRF) produced by dry fractionation. This contained (g/kg) 446.2 of protein and 345.2 of nitrogen-free extract. The maximum nitrogen solubility was 60% at alkaline pH and the minimum was 11.7% at pH 4. The emulsifying activity ranged from 50 to 56% and was independent of pH. Emulsion stability was highest (92%) at pH 8 and 10. SPRF was not a good foaming agent, with a maximum of 29% and no dependence on pH. However, foam stability was good (80%). Diluted solutions (30 and 40 g/L) exhibited high apparent viscosity (10,000 cP) with typical non-Newtonian fluid behavior. The SPRF is a potential food ingredient, particularly in foods requiring emulsion or foam stability.