OPTIMIZATION OF SUPERCRITICAL-FLUID CONDITIONS FOR THE RAPID-DETERMINATION OF FREE FATTY-ACIDS IN SOY AND COTTONSEED MEALS

An alternative extraction method for the determination of fatty acids in cottonseed and soy meals employing supercritical carbon dioxide mod ified with methanol is described. Higher free fatty acid levels are an indicator of meals that have deteriorated in storage and may influenc e fermentation yields negatively. The extraction conditions were optim ized using ''design expert'' software. Several optimum conditions for a quantitative extraction were determined. The addition of methanol in creased the extraction yield considerably, which is demonstrated with the help of three-dimensional plots of recovery versus modifier and pr essure while temperature was kept constant.