Liquid chromatographic method for quantitative determination of free fatty acids in butter.
A liquid chromatographic method has been developed for the determination of free fatty acids in butter. The fatty acids are converted to the p-bromophenacyl esters, via a crown ether-catalyzed reaction, without separation from the other butter components. The esters are separated on a C18-bonded silica column by using an acetonitrile-water solvent gradient and quantitated using the ester of heptadecanoic acid as internal standard. C16 and C18:1 co-elute in the acetonitrile-water system but are separated using an isocratic methanol-acetonitrile-water system. Limits of detection range from 7 ng for butyric acid to 45 ng for linoleic acid. The average coefficient of variation (n = 10) for 10 free fatty acids from a butter was 5.83%.
D000098:Acetophenones / Q000032:analysis; D000818:Animals; D002079:Butter / Q000032:analysis*; D002417:Cattle; D002853:Chromatography, Liquid / Q000379:methods; D005230:Fatty Acids, Nonesterified / Q000032:analysis* / Q000378:metabolism
D000098:Acetophenones; D005230:Fatty Acids, Nonesterified; D002079:Butter; C006821:4-bromophenacyl bromide