Trans octadecenoic fatty acid (TFA) isomers in German foods and bakery goods

Abstract

In the present study, 122 food samples from the German food market were analysed for their C18:1 trans fatty acid (TFA) content and profile. A particular focus of the survey were baked and fried foods. TFA analysis was performed by means of silver ion SPE (Ag+‐SPE) in combination with high‐resolution GC (HRGC‐FID). Overall, 51 bakery product samples were analysed of which 25 samples were prepacked bakery products purchased from local retail stores and 26 samples of unpacked bakery products purchased from local bakery shops. In addition, 14 French fries samples obtained from small local fast food restaurants as well as from internationally operating fast food chains, 27 potato and tortillas chips, 15 instant soups as well as 15 dry culinary sauces were analysed. The highest amounts of C18:1 TFA isomers were found in deep‐fried bakery products. Prepacked branded cookies and biscuits on the other hand contained only negligible C18:1 TFA amounts. Regarding their C18:1 trans isomer profile most deep‐fried bakery products exhibited a Gaussian‐distributed isomer profile. The analysed prepacked croissants, cookies and biscuits contained predominantly ruminant TFA (TFA) as suggested by the presence of vaccenic acid (C18:1 trans 11), which was the major C18:1 TFA isomer in these products. All non‐bakery samples (n = 71) contained less than 3 g C18:1 TFA per 100 g fat. In conclusion, TFA still occur in considerable amounts in a few German food products, especially in some deep‐fried bakery products (‘Berliner’ type of doughnuts). Practical applications: Trans fatty acids, in particular the trans octadecenoic fatty acid isomers (C18:1), are generally considered from the nutritional point of view as undesirable food components due to their negative health effects. Tremendous efforts have been made by major food processors in order to decrease or even eliminate the presence of TFA in some foodstuffs (e.g. in margarines in European countries). However, some food processors of other food sectors are still applying oils and fats containing partially hydrogenated vegetable oils, whereas others within the same food category have already switched their processing conditions and/or raw materials towards TFA alternatives. Therefore, actual TFA data of foodstuffs determined by means of state‐of‐the‐art analytical procedures (Ag+‐SPE in combination with GC‐FID) is necessary to detect areas of further improvement in the food supply chain and to provide data for an update of dietary TFA intake.

Trans fatty acids in the Portuguese food market

“…In that survey, the highest mean values were also observed in fine bakery products and snacks, cakes and biscuits, with means around 6% and 4%, respectively. In Germany, two recent studies also revealed high amounts of TFA in bakery products and confectioneries, with up to 27% in bakery products in the first ( Fritsche et al., 2010 ), and up to 40% of TFA in the second ( Kuhnt et al., 2011 ). These authors also concluded that unpackaged bakery products had higher amounts of TFA compared to packaged ones, as observed in the present study.…”

“…In the absence of a representative national nutrition survey, with ingestion patterns and relative contributions to fat consumption, a preliminary desk review was performed on literature data, aiming to identify the food categories with potentially higher amounts of TFA from industrial origin in other countries ( Hulshof et al., 1999 , Chiara et al., 2003 , Craig-Schmidt, 2006 , Stender et al., 2006 , Baylin et al., 2007 , Ledoux et al., 2007 , Griguol et al., 2007 , Wagner et al., 2008 , Richter et al., 2009 , Fritsche et al., 2010 , Remig et al., 2010 , Cakmak et al., 2011 ; Hissanaga et al., 2012 , Roe et al., 2013 , Saunders et al., 2008 ). The following food categories were selected: bakery/breakfast cereals, biscuits/wafers/cookies, bouillon cubes, butter, chocolate snacks, chocolate spreads, fast food, instant desserts, instant soups, margarines/shortenings, pastry, popcorn, and potato chips/French fries.…”

What are the trans fatty acids issues in foods after discontinuation of industrially produced trans fats? Ruminant products, vegetable oils, and synthetic supplements

“…In the last few years, however, the use of industrially produced TFAs has dramatically decreased in Switzerland , Austria , Germany , the United States , and Canada . In practically all food products iTFAs showed a decline except for certain foods such as cookies, biscuits, bakery products, cake mixes, shortenings, and frozen foods that still contain high amounts of TFAs in some regions of the world.…”

Development and technofunctional‐sensory characterization of virtually TFA free deep‐frying fats for artisan bakery products

“…In 2008, the German Federal Office of Consumer Protection and Food Safety (BVL) analyzed bakery products from German bakeries and found an average TFA content of 12.8% of the total fat in 40 out of 74 donuts and certain pastries [9]. These findings were confirmed by Fritsche et al [10,11] who determined TFA contents of sometimes more than 25% of total fat in deep-fried bakery products purchased from local artisan bakeries. Likewise, Br€ uhl and Unbehend [12] determined TFA levels of at least 25-32 g/100 g in donuts deep-fried in PHPO containing 42.5% TFA.…”