Exploitation of the selectivity of various chromatographic techniques for the study of the triglyceride structure of natural fats

The separation of naturally occurring triglyceride mixtures on the basis of mol wt, polarity, and iodine number by the methods of gas‐liquid, liquid‐liquid, and thin‐layer chromatography, respectively, rarely results in fractions representing pure triglycerides. Furthermore, most of the fractions obtained are too complex for detailed structural analyses. An integrated system using all three of these techniques for a sequential fractionation and isolation of triglyceride groups of progressively decreasing complexity, however, while not yielding single glycerides, can provide practical information for the assignment of structures. Since the possibility of the same components overlapping in all three systems is very small, a prudent application of these techniques affords triglyceride groups that can be analyzed meaningfully by enzymatic methods, and, in many cases, can lead to a complete assessment of the triglyceride structure of the mixture. For an examination of the scope of this integrated analytical system, selected naturally occurring triglyceride mixtures were used as models. The success of the system rests upon accurate quantitative determination of the fatty acids and triglycerides by gas chromatography.