SOAP/SHAMPOOS/DETERGENTS Today, little soybean oil or soybean soapstock (the sodium salt of the free fatty acids separated from the soybean oil during neutralisation) is used in soaps. Soybean soapstock is mostly used in animal feed and small amounts are used as dust suppressant. Fatty acids recovered from soybean soapstock are used in some liquid soaps for laundry, shampoos and dry cleaning. Soybean oil and soybean fatty acids are used to manufacture surface-active compounds. A number of soy fatty amines are used as surfactants. High unsaturation and high price of soybean oil make alternative animal-derived fats often more interesting.