The separation and identification of the components in milk fat, which are mainly triglycerides, is a challenge due to its complex composition. A reverse-phase high-performance liquid chromatography (HPLC) method with gradient elution and light-scattering detection is described in this paper for the triglyceride analysis in ewes' milk fat. Triglyceride identification was carried out by combining HPLC, gas-liquid chromatography (GLC), and the calculated equivalent carbon numbers of several triglyceride standards. Quantitation of partially resolved peaks in the HPLC chromatogram was accomplished by applying a peak deconvolution program. Forty-four fatty acids were identified by GLC analysis, but only 19 were used for the following prediction of triglyceride molecular species; 181 triglycerides were identified, some of which were grouped at the same peak and needed application of the deconvolution program. Consequently, coefficients of variation were close to or lower than 5%. Moreover, the triglyceride composition of ewe, cow, and goat milk fat were compared by using these methods. These results show that ewe milk fat is richer in shortand medium-chain triglycerides, and cow milk fat is richer in long-chain and unsaturated triglycerides.JAOCS 73, 283-293 (1996).

A total of 116 molecular species of triglycerides were identified in milk fat, using a combination of HPLC and GLC. Triglyceride composition was predicted from the random composition, which was calculated on the basis of the mole fractions of the main fatty acids making up the total triglyceride fraction. The qualitative composition of the milk fat was similar in cows', ewes' and goats' milk. In all three milks the partition number of the main triglycerides was 46, but the proportions of the triglycerides with partition numbers of 34, 38, 42, and 48 exhibited substantial differences among the milks of the three species.

The fatty acid composition of seeds ofGinkgo biloba has been examined by a combination of capillary gas chromatography, silver ion high‐performance liquid chromatography and gas chromatography/mass spectrometry. Some of the fatty acids identified are unusual in plants and were rather different from those reported earlier. These include ananteiso‐methyl branched fatty acid, 14‐methylhexadecanoic acid, 5,9‐octadecadienoic acid, and 5,9,12‐octadecatrienoic acid. Fourier‐transform infrared spectroscopy confirmed that all of the double bonds were of thecis‐configuration.

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