Effects of roasting on the characteristics of australian wattle (Acacia victoriae Bentham) seed and extracts

Abstract

The effects of roasting at 200°C for up to 30 min on the color, chemical composition, and trypsin inhibitor activity of wattle seed (Acacia victoriae Bentham) and its extracts were studied. Results showed that roasting induced significant (p < 0.05) changes in color difference index (ΔE*ab) of flours compared to seeds. Furthermore, chemical analysis showed that protein solubility decreased as a result of roasting. Polyacrylamide gel electrophoresis and reverse phase high performance liquid chromatography of soluble proteins showed that large molecular weight polypeptides were rapidly broken down, with resultant formation of smaller, more hydrophilic fragments. Both total and soluble carbohydrates decreased during roasting, most likely due to Maillard-type reactions and caramelization, and polyacrylamide gel electrophoresis and spectrophotometric assays confirmed the essential elimination of trypsin inhibitor activity after 20 min of roasting. Copyright © 2013 Taylor & Francis Group, LLC.