CONTENT OF TRANS C18:1 AND TRANS C18:2 ISOMERS AND CIS9TRANS11 C18:2 (CLA) IN FAT BLENDS

Abstract

The content of trans C18:1, trans C18:2 and cis9trans11 C18:2 (CLA) in the marketed fat blends was evaluated by capillary gas chromatography and silver thin-layer chromatography. For comparison, the level of these acids was also determined in commercial butter, purchased at the same time. The content of trans C18:1 in fat blends showed that half of the examined products contained trans C18:1 at 1.9-4.4%, while the other half contained 8.2-24.2% trans fatty acids. The fat blends with a high total content of trans C18:1 were characterized by a high proportion of trans 6-8 and trans 9 isomers. The trans 9 C18:1 in these products constituted 15.0-22.5% of the total trans C18:1. The level of trans C18:2 in fat blends examined ranged from 0.3 to 1.1%. Seven of the 18 tested fat blends contained, apart from cis-trans and trans-cis C18:2, also trans-trans C18:2 in the 0.03-0.4% range. In all fat blends examined, CLA was present. The products with a low level of trans C18:1 contained CLA at 0.3-1.0%. The content of CLA in the fat blends with high level of trans C18:1 did not exceed 0.3%.

Properties and biotechnological methods to produce lipids containing conjugated linoleic acid

“…The products with a low level of trans 18:1 contained CLA at 0.3-1.0%. The content of CLA in fat blends with high levels of trans 18:1 did not exceed 0.3% [56]. Analysis of the fatty acid composition in French butters indicated that the average CLA content was 0.45 g/100 g butter in winter, 0.58 in spring and 0.80 in summer [57].…”

The effect of storage on the yogurt fatty acid profile

“…The level of CLA in milk fat mainly depends on the feeding period, as well as lactation period, breed and individual determinants of cows. According to literature data (Kelsey et al, 2003;Żegarska et al, 2006;Zunong et al, 2008;Frelich et al, 2012;Hanuš et al, 2016) higher contents of this fatty acid occur in fat of milk from the summer season and lower contents in milk fat from the winter season. The content of CLA in dairy products (fermented milk or cheeses) may differ from that in milk.…”