Absolute quantification of fatty acid and proximate composition of cow and goat powdered milks

Abstract

This work investigated of the lipid quality of processed milks by fatty acid quantification. Ten samples of dry whole milk from cow and two from goat were submitted to total lipid extraction and to fatty acid methyl ester synthesis. Then, the synthesized products were separated in a gas chromatograph. The variation of the fatty acid per total lipid gram for polyunsaturated compounds, omega-6, omega-3 and conjugated linoleic acid, was 25.20-46.67, 12.82-31.45, 1.77-7.65 and 7.77-11.60, respectively. The n-6/n-3 ratio for the cow powdered milk samples (2.85-6.07) was lesser reagarding goat milk samples (11.31-12.75) and the trans fatty acid amount varied from 0.09 to 0.17 g per 26 g portion. Essential fatty acids from the omega-3 and omega-6 groups were present in every sample, besides conjugated linoleic acid isomers. The trans fatty acid contents of the samples is in accordance with the Brazilian legislation. © 2012 Sociedade Brasileira de Quimica.