unsaturated fatty acids are believed to possess pro-salubrious properties and isomers
of the conjugated linoleic acid (CLA) belong to this group. Foods with high level of
biologically active compounds (e.g. CLA) are frequently referred to as functional
foods. The definition ‘functional food’ describes products containing components
that except traditional functions (e.g. energetic role of fat) play other, important roles
[Dugganet al. 2002]. The role and function that individual CLA isomers can play
is still investigated with novel analytical methods. Supplementation of diet of dairy
cows with plant oils and/or fish oil can change mutual proportions between fatty acids
of milk, reducing the content of saturated and increasing that of unsaturated fatty
acids, including conjugated isomers of linoleic acid [AbuGhazaleh et al. 2002, 2003,
Newbold et al. 2004]