FUNCTIONAL-PROPERTIES AND AMINO-ACID-COMPOSITION OF SOLVENT-EXTRACTED FLAXSEED MEALS

The functional properties of solvent-extracted flaxseed meals were studied. The solvent systems employed consisted of hexane and absolute or 95% (v/v) alkanol with or without 10% (w/w) ammonia. Approximately 55% of the total nitrogen-containing compounds present in the meals were dissolved in water Meals extracted with methanol-ammonia-water/hexane had the highest nitrogen-solubility index. The minimum solubility of nitrogenous compounds in hexane-extracted and methanol-ammonia-water/hexane-extracted meals occurred between pH 3.0 and 3.5. Flaxseed meals had a high water-adsorption value, and the two phase solvent extraction did not influence it. Fat adsorption of the meals was influenced by the presence of ammonia in the extraction system, and the pH of these meals was increased by nearly one unit. Solvent-extracted flaxseed meals had improved emulsifying and foaming properties. Extraction with ammonia-water/hexane did not change the amino-acid composition of flaxseed meals.