CONTROL OF MILK-FAT PURITY BY GAS-CHROMATOGRAPHIC TRIGLYCERIDE ANALYSIS

Different methods are described for the extraction of milk fat for the triglyceride analysis, for the optimal preparation of columns, together with suitable conditions for the gas chromatographic high-temperature analysis of triglycerides as well as a sensitive detection method of non-milk fats in milk fats using triglyceride formulae. Along with a number of new suggestions for improvements (e.g. suitable carrier gas rates, column temperatures depending on the length of the column, avoidance of baseline rise at high column temperatures and of discrimination of high-boiling triglycerides, flawless integration of the chromatograms), the areas of application of this method are listed, and the independence of the triglyceride formulae from milk fats, which may vary considerably in their composition due to feeding conditions, is shown. By inserting defined triglyceride contents of a fat to be analyzed in such triglyceride formulae, it is possible to detect 1-5% vegetable and animal (hydrogenized fish oil, lard, beef tallow) foreign fat additions depending on the type of foreign fat. By this method quantitative informations about non-milk fat additions in milk fat can also be obtained.