Functional properties of processed Australian wattle (Acacia victoriae Bentham) seed extracts

Functional properties of water extracts from processed prickly wattle (Acacia victoriae Bentham) seed flours were compared to those of raw flours and an ammonium sulphate precipitate (ASP) containing >77% protein. All extracts formed stable 20% and 50% (v/v) oil-in-water emulsions at concentrations between 1% and 5% (w/v) but the emulsions formed from processed flour at low extract concentrations destabilized by oiling off within 7 days at 25 °C. Comparatively, emulsions formed with 5% raw and processed extracts creamed or broke reversibly. Conversely, ASP-stabilized emulsions were very stable at all concentrations and conditions in this study. However, all extracts and ASP had poor foaming capacity and did not gel even at up to 10% solids concentration. The results indicated that processing of wattle seeds for flavour enhancement or destruction of anti-nutrients led to poorer functionality. The excellent emulsifying and emulsion stabilization properties of ASP could potentially be exploited in processed foods.