Soybean soapstock is derived from vegetable oil refining and is the cornerstone of Feed Energy products. Soapstock is produced through chemical bonding — with a caustic such as sodium hydroxide — of the minute amounts of specific fatty acids from the crude oil in the vegetable oil refining process. Soapstock also will contain whole vegetable oil and the gums from the degumming process. In addition, soapstock has a high concentration of tocopherols (Vitamin E and antioxidants), pigments (carotenoids) and phytosterols. Acidulated soapstock has a highly concentrated amount of free fatty acids, which compresses the most metabolic energy possible into a pound of oil.