Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 11/14/1997
Publication Date: N/A
Technical Abstract: During the past 50 years, research on vegetable oil processing has been directed toward determining causes of oil instability and investigating methods to increase stability. Researchers in the 1940's and 1950's determined that metals and linolenic acid were major causes of oil stability. Subsequent investigations discovered that citric acid and hydrogenation were effective in extending oil stability. More recently, scientists have investigated alternatives to traditional extracting, degumming, refining and hydrogenating processes. Alternative solvents to hexane have included hexane-ethanol azeotrope, isopropyl alcohol, heptane, supercritical carbon dioxide, and expander technology. Researchers have found that these methods are better than or equal to hexane in extraction capabilities; however, cost is usually higher. New methods for degumming include ultrasonic treatment, microwave heating, steam treatment and the Alcon process. Steam refining and use of supercritical CO2 during refinin have also been studied. Alternatives are being studied to traditional processing and utilization procedures that provide oils with increased stability in food applications. For example, electrochemical hydrogenation is an alternative to traditional hydrogenation that decreases double bonds but only produces low (3-4%) levels of trans fatty acids. Interesterification is also an effective method to prepare margarines and shortenings with zero trans fatty acids. Finally, genetic modification of oilseed fatty acid composition has potential to provide functional and high stability characteristics utilizing low-linolenic/mid-oleic oils for frying oils and high-stearic soybean oil for margarine and shortening.