Composition and Distribution of Lipids of Goats’ Milk

Abstract

Fresh commercial goats’ milks were examined for their lipid contents and distribution of these lipids among milk fractions. Whole milk, skim milk (produced by centrifugation at 330 and 2,000 × g), and cream were studied. Petroleum ether (free lipids) and chloroform methanol (2:1) (bound lipids) were used successively to extract the lipids from all milk fractions. Average total lipid content for five bulk milk samples was 5.0 ± 1.2%. Lipid fractions of whole milk and cream contained 97 to 99% free lipid and 1 to 3% bound lipid, respectively. Free lipid was 96.8% triglyceride, whereas bound lipids contained neutral lipid, glycolipid, and phospholipid. In this respect, goats’ milk resembled cows’ milk. However, goats’ skim milk fractions contained significantly more free lipid than did cows’ milk. This free lipid, investigated in detail by gas chromatography, was shown similar in triglyceride distribution and fatty acid content to whole goats’ milk triglyceride. Quantitative data for the triglyceride distribution in all fractions are given and differ from published data for fresh goats’ milk. © 1982, American Dairy Science Association. All rights reserved.