Elaidic acid, a transdiomer of oleic acid (DAC86), is an unsaturated fatty acid. In its pure state, it is a colourless, oily liquid that is hardly soluble in water and easily oxidises in air, turning into a yellowish liquid and smelling rancid. Salts of oleic acid are known as oleates.
Oleic acid dissolves well in methyl alcohol, ethyl alcohol, diethyl ether and fatty and essential oils. During fat hardening, oleic acid is converted into stearic acid.
Oleic acid is the most important unsaturated, essential fatty acid in food. It is found in olive oil and sunflower oil. With the elaidic acid there is a cis-trans isomerism. In cosmetic products oleic acid serves as acid component of emulsifiers