La genuinità del grasso di latte di bufala: un'applicazione del Metodo Ufficiale UE (Precht) basato sulla determinazione gascromatografica dei trigliceridi

THE PURITY OF WATER BUFFALO MILK FAT: AN APPLICATION OF THE EU METHOD (PRECHT) BASED ON THE GAS CHROMATHOGRAPHIC DETERMINATION OF TRIGLYCERIDES Milk fat purity is presently evaluated by the gas chromatographic determination of triglycerides by the Official Method of the European Community. This method allows the detection of foreign fats, of both animal and vegetable origin, in milk fat. It is based on the determination of the triglycerides with even carbon number and on the subsequent application of formulae deriving from multiple linear regressions for the calculation of five “S” parameters. The results obtained by this calculation are compared to the limits fixed for a 99% confidence interval. The aims of this work were: a) to determine the suitability of this method to water buffalo milk fat b) to propose a modification to the method for evaluation of water buffalo milk fat purity c) to determine the sensibility of the method for the detection of non lactic foreign fats in water buffalo milk 250 samples of water buffalo milk fat were extracted from milk of guaranteed origin. The water buffalo milk was kindly supplied by a livestock breeding factory in Caserta and Salerno. In order to validate this method, 100 samples were further utilized. The results show that it is necessary to modify the limits formula of Precht method to determine the purity of water buffalo milk fat. The modified UE method allows the detection of 5% non lactic foreign fat in water buffalo milk fat.