Trans fatty acid content of selected Swiss foods: The TransSwissPilot study

The objective of this study was to analyse the trans fatty acid (TFA) content of a selection of foods sold on the Swiss market in order to get an overview of the situation and to find indicators to assess the origins of TFA. 119 food items from different food groups were purchased in the city of Zurich and analysed for their TFA content with gas chromatography. TFA were detected in all but two samples and the content ranged from 0 to 29% of the total fat. Nearly 40% of the analysed samples had more than 2% TFA. The highest mean value was observed in the fine bakery products (6% TFA) and the lowest with the breakfast cereals (<0.4% TFA). Trans-C18:1 was the predominant TFA in all samples except for the plant oils, in which trans-C18:2 and trans-C18:3 isomers made up the bigger part of the total TFA content. An analytical distinction of the TFAs according to their origin seems possible when concomitantly considering the amounts of t11-C18:1, c9,t11-C18:2, and total TFA. The situation regarding the TFA content in Swiss food was similar to many other countries worldwide.