Gas–liquid Chromatographic Analysis of the Triglyceride Composition of Molecular Distillates of Butter Oil

A quantitative gas–liquid chromatographic analysis of the triglycerides of butter oil and its distillates has shown that molecular distillation can effect a significant fractionation of butterfat. The most volatile 2.5% distillate contained nine triglyceride types (C24–C40), six of which were present in concentrations representing 3- to 20-fold enrichments, when compared with the original oil. Eighty-six percent of the C30and shorter triglycerides occurred in the most volatile fractions, which comprised 5% of the total fat. The residue, which represented 50% by weight of the oil, contained 10 triglyceride types (C36–C54), seven of which were present in concentrations exceeding those in the original oil. This residue contained 93% of the triglycerides longer than C46. The other distillates contained triglycerides the mean molecular weights of which increased with decreasing volatility. In all cases the triglyceride composition of the butter-oil distillates was markedly different from that of butterfat.