Quality control of butter by means of capillary column RTX 65-TG

In this paper a new analytical method for the detection of extraneous fats fraudulently added to butter is proposed. Such determination is carried out by gas chromatographic analysis of butter triglycerides, using a capillary column for triglycerides having 65% phenyl methyl silicone as stationary phase. During the last twenty years, different methods for evaluation of butter genuineness were proposed. The presence of vegetable oils mixed with butter is based on sterol analysis; the revelation of vegetable sterols in butter represents a clear evidence of fraud. The Official EU method for detection of animal fats in butter, as lard and tallow, is time consuming, it often brings to not easily reproducible results and it is not of great accuracy especially in the cases of small additions of extraneous fats. The method proposed in this paper allows to detect the presence of extraneous vegetable and animal fats in a simple, rapid, and precise way, even if the quantities added to butter are minimum. The analysis is based on the best resolution, actually achievable, of single triglyceride components and their comparison with those present in certainly genuine butters, taken as reference.