Comparison of Extraction Methods for Fatty Acid and Conjugated Linoleic Acid Quantification in Milk

The purpose of this study was to compare acid and base catalyst for the extraction of Fatty acids (FA) and conjugated linoleic acid from milk product. Lipid extraction from milk by using acid catalyst were carried out in H₂SO₄/methanol solvents. Methylation was performed for 2 h at 80°C, and FA methyl esters were recovered for chromatographic analysis by the addition of isooctane. On the other hand, the extraction using base catalysts was conducted by AOAC 989.05 (2012) official method, followed by AOAC 969.33 (2012) for methylation. Extraction process by acid catalyst shown better performance compared to base catalyst due to it could be produced higher recoveries. The advantage of extraction method by using acid-catalyst allowed the measurement of high number of samples. Moreover, it can be reduced the sample manipulation and consequently reduce sample loss and contamination. In conclusion, the acid-catalyst method was a simple and rapid method, low cost, and achieves good results for Fatty acids (FA) and conjugated linoleic acid extraction from milk product.