A reversed-phase high-performance liquid chromatographic method for the determination of soya bean proteins in bovine milks

A reversed-phase high-performance liquid chromatographic method was designe d for the quantitation of soya bean proteins in bovine milks. The method co nsisted of a linear binary gradient, acetonitrile-water-0.1% trifluoroaceti c acid, at a flow rate of 1 mL/min and a temperature of 50 degrees C which resulted in a separation time for soya bean proteins of 11 min. Calibration by the external standard method using a soya bean protein isolate as stand ard was employed, and the method was validated by evaluating precision, acc uracy, and robustness. This method was shown to be useful for the analysis of soya bean proteins in bovine milks spiked with soya bean protein isolate ; soya bean protein concentrations of similar to 13 mu g/g of bovine milk c ould be detected by using the optimized method. The results obtained for so me of the bovine milks were compared with those obtained by the method of s tandard additions.