Abstract: There is a mounting concern about the intake of foods containing TFA due to their deleterious effects on human health, mainly on the cardiovascular system. It is however important to brighten the processes that lead to the formation TFA in foods, and the alternatives to minimize them. In our study we studied the influence of added natural antioxidants (rosemary extract (Rosmarinus officinalis L.) and lutein) to the vegetable sunflower oil on the formation of trans fatty acids (TFA) during heat treatment. The experiment included: 1.0g rosemary extract per kg oil (SOR), 0.1g lutein per kg oil (SOL) and control sample (SO). The changes in fatty acids (FA) compositions were evaluated using gas–liquid chromatography (GLC) and AG-Ion SPE separation. The content of total polar compound (TPC) was analyzed using a Testo 265 based on dielectric constant measurement. In our study we emphasize the effect of heat on TFA with 18 carbon atoms. The content of trans C 18:1 increased from 0.67±0.08% at the beginning to 1.12 ± 0.14% in SO, to 0.99±0.04 in SOR and to 0.91±0.01 in SOL at the end of heat treatment. The differences was statistically significant (P

Sebastjan Filip¹, Rajko Vidrih²

¹PhD student, ²professsor assistant

Keywords: polar content , oil , trans fatty acids