Analysis of the glyceride structure of cocoa butter by thermal gradient crystallization

Cocoa butter was separated into 43 fractions by crystallization in a thermal gradient. Similar fractions were pooled and converted into methyl esters which were analyzed by gas‐liquid chromatography. The amount of cocoa butter separated into a pure glyceride type was 85%. No significant difference was found in the ratio of palmitic to stearic acid in the GSU 2 and GS 2 U. In the GS 2 U, ternary and binary eutectic mixtures are predicted by the ideal solution theory. When the eutectics are taken into consideration, the individual glyceride composition of cocoa butter agrees well with the composition predicted by restricted random distribution. To test the ability of thermal gradient crystallization to separate GU 3 and GS 2 U a sample of cocoa butter plus 10% triolein was analyzed. The apparent composition of the cocoa butter and triolein indieated that the GU 3 and the GS 2 U separation was incomplete.