Squalene in oils determined as squalane by gas-liquid chromatography afterhydrogenation of methyl esters

Low levels (less than or equal to 0.1%) of squalene were anticipated in oil s from the blubber of the harp seal Phoca groenlandica. The traditional rou te of saponification and analytical examination of the total unsaponifiable s was unattractive. A method developed for squalene in olive oil, reportedl y present in the range of 0.3-0.7%, was based on total conversion of the oi l to methyl ester of fatty acids by alkali transesterification, followed by hydrogenation over Adam's catalyst (PtO2) The analysis of the fully satura ted methyl esters and any squalane produced concurrently was by gas-liquid chromatography. This method was satisfactory for the small amounts, 0.03% o r less, of squalene in seal oil and is also illustrated for olive oil. A fl ame-ionization detector excessive response of approximately 25% was observe d for all levels of squalene tested. The calculated factor of 1.22 should b e applied to the peak area for squalane due to the higher response of hydro carbons relative to the methyl esters of fatty acids and the system of oil components if reporting as fatty acids.