Submitted to: Annual Meeting and Expo of the American Oil Chemists' Society
Publication Type: Abstract Only
Publication Acceptance Date: May 15, 1997
Publication Date: N/A
Technical Abstract: Stable dispersions of oils and lipid materials in aqueous media are difficult to prepare and typically require the addition of surface-active agents or emulsifiers to inhibit phase separation. We have now observed that stable products may be prepared from starch, water and oil by a steam jet cooking process that utilizes the high temperature and turbulence within the cooker to uniformly distribute the oil component within the aqueous starch matrice as micron-size droplets that do not coalesce and separate, even after prolonged standing. Surface-active agents are not needed. Compositions typically contain 20-50 parts of oil per 100 parts of starch, by weight, and may be prepared from a wide variety of vegetable oils, lipids and water-insoluble organics. Drum drying is a practical method for isolating these compositions and produces outwardly dry products that are not oily to the touch. No agglomeration or separation of dispersed oil is observed when dried products are redispersed in water. A significant percentage of the oil component is tightly held within the starch matrix and cannot be easily extracted with hexane. Oil droplet size can be reduced by 1) addition of protein, 2) multiple passes through the steam jet cooker, 3) increasing steam pressure during jet cooking, and 4) an "add-back" procedure. Starch-oil compositions have practical applications as fat replacers in food products, and as components in adhesive, seed coating, cosmetic, and oil-drilling formulations. The technology has been licensed by the private sector, and we are cooperating with companies to prepare products suitable for marketing.