Trans isomers of fatty acids may be formed during industrial fat and oil processing and naturally during biohydrogenation by rumen microorganisms in the ruminants. The aim of our study was to determine fatty acid level, particularly trans isomers of fatty acids in randomly selected 32 samples of infant formulae and follow-up formulae in 2009 in Poland. The fatty acid methyl esters (FAME) were analyzed by high-resolution capillary gas chromatography (GC/MS). The average content of trans fatty acids (TFA) amounted to 0.25% wtlwt (range 0.17-0.33% wt/wt) in infant formulae and 0.28% wtlwt (0.18-0.40% wtlwt) in follow-up formulae. There was no significant difference between trans fatty acids content in infant formulae and follow-up formulae. In TFA group the main fatty acid was trans 18:2 making up over a half of all trans isomers in both of formulae and next trans 18:3 (over 30%). The high level of above-mentioned trans isomers is pointing out on presence, mainly, vegetable oils in fat fraction of infant formulae milks. In conclusion, the trans fatty acid level in all analyzed products do not exceed 0.4% of fat so we confirm that they are safe for infants, who are not breastfed.
This study was aimed at determining lipid content, fatty acid composition and trans isomers content in fat extracted from cereals and cereal bars. Cereals and cereal bars were analyzed by gas chromatography. Analyses showed that they were characterized by a diversified content of fat and composition of particular groups of fatty acids (saturated SFA, monounsaturated MUFA and polyunsaturated PUFA). Only oat flakes turned out to be a good source of PUFA (38.83% of total fatty acids). The remaining products contained more SFA (mean: 45.12% and 47.73% in cereals and 63.31% in cereal bars) than PUFA (mean: 12.24% and 16.73% in cereals and 7.83% in cereal bars). Lipid of all examined products contained trans isomers of C18:1 and C18:2 acids. In lipids of cereals, the total content of these isomers did not exceed 0.5% of the total fatty acids. A higher content of these isomers was found in cereal bars (0.45–3.15%).
For development of zero trans baking shortenings enzymatic interesterification was applied. Both immobilized (Novozym 435, Lipozyme RM IM, Lipase PS “Amano” IM) and native (Lipase A “Amano” 12, Lipomod TM 34P) enzymes were applied as biocatalysts. Palm stearin was explored as a source of palmitic acid. The immobilized enzymes formed new asymmetric triacylglycerols containing palmitic acid. The interesterification process produced the zero trans fats with the solid fat content profiles closely matching those of the commercial baking shortening. Not only did the novel structured lipids have comparable physical properties with the commercial baking shortening, but also offered additional health benefits. Thus enzymatic interesterification with immobilized lipases offered great potential in production of fats with expected properties.
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The present study was designed to investigate the hypothesis that trans fatty acids can induce apoptosis of human umbilical vein endothelial cells (HUVEC). To test this hypothesis apoptosis was measured in HUVEC treated with 0.1, 1.0 or 5.0 mM trans elaidic acid (t-18:1) or linoelaidic acid (t,t-18:2) for 24 hours. For the detection of apoptosis, TdT-mediated dUTP nick end labelling assay (TUNEL), cell binding of annexin V and propidium iodide uptake were measured. Active Caspase-3 and cleaved PARP (poly-ADP-ribose polymerase) were also measured in the cell lysate. Moreover, cellular ability to produce ROS (reactive oxygen species) was measured by DCF fluorescence Both acids studied induce both early (annexin-positive cells) and late stages of apoptosis (cells stained by propidium iodide) in a dose-dependent manner. Also the appearance of TUNEL-positive cells was induced by both trans fatty acids tested, in a dose dependent manner. Both trans acids induce apoptosis through their effect on Caspase-3 activity and on intracellular ROS production. It is worth emphasising that linoelaidic acid proved to be a more potent inducer of apoptosis and ROS production in endothelial cells than elaidic acid. The present studies suggest that trans fatty acids may play a role in damaging and death of vascular endothelial cells in atherosclerosis.
The trans fatty acids in milk fat from the indoor feeding ( March, April) and the pasture feeding period (May) were determined. An argentation thin layer chromatography (Ag-TLC) and gas liquid chromatography (GLC) on a polar capillary column (CP Sil 88) were used.The content of trans fatty acids in milk fat showed considerable seasonal variations. The trans 18:1 content for the pasture period was 5.73 g/100 g milk fat (MF) and only 1.83 g/100 g MF for the indoor feeding period. About one-half of trans 18:1 isomers in the samples from the indoor feeding period and more than 60% in the samples from May was trans-11 18:1 acid. The level of two trans 18:2 isomers (cis-trans and trans-cis) was about 4 times higher (0.81 g/100 g MF) in the pasture feeding period than in the indoor feeding period (0.18 g/100 g MF).
Effects of inuline used as partial fat replacement in cookies containing three different fats were studied. During experiment sensory and instrumental attributes of reference cookies and low fat formulation in which 50% of fat was replaced with inuline were compared. Shortenings used for preparation of cookies differed greatly in saturated fatty acids (SFA) (29.9–57.5%), trans fatty acids (TFA) (0.9–23.1%) and solid fat content (SFC) at 25°C (13.6–31.6%). Replacement of 50% fat with inuline in the formulations enabled obtaining samples with higher instrumental values of texture and resulted in cookies which were harder and less crispy. Also the intensity of sweet taste was sharply reduced by decreasing the fat content of cookie recipes. On the other hand, replacement of 50% of fat with inuline had a little impact on the intensity of buttery taste of the cookies. The lowest intensity of buttery taste was scored in cookies containing shortening with the lowest content of TFA. Concerning the overall sensory quality, the results showed that the replacement of 50% of fat with inuline resulted only in a moderate decrease in the acceptability of the overall sensory quality. The averaged scores of overall sensory quality were generally high and ranged from 7.1 to 9.1. In conclusion, it has been demonstrated that inuline was suitable for inclusion in cookies, as a fat replacer and as a functional ingredient.
Quantity and quality of fat in every day diet influence human health. Recently particular attention is payed to trans fatty acids composition in ingested food. Modern, no time consuming, convenient food is widely used now. Seventeen chosen products like dry soups or sauces mixes from the market in Poland were analysed to estimate fat concentration and fatty acids composition including trans fatty acids. The products contained different amount of fat, from about 3g/100g to 24g/100g of product. The fat concentration as well as fatty acids composition varied dependently on the kind of product and producer too. The dominated group of fatty acids in all analysed samples were saturated fatty acids (up to 50%). Monounsaturated fatty acids occured in the range from 15 to 40%, while polyansaturated from 2 to 6%. Four trans fatty acids were identified: 18:1, 6-trans, 18:1, 9-trans, 18:1, 12-trans, and 18:2, cis-9, trans-12. Only 18:1, 9-trans.
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It has been shown that increased intake of trans fatty acids (TFAs) is associated with a higher risk of cardiovascular disease. In this study, we have investigated the effects of linoelaidic (LA) and elaidic (EA) acids on the proinflammatory response in endothelial cells, a key step in vascular disease. Human aortic endothelial cells (HAECs) were treated with different concentrations (100 µmol/l in most experiments) of LA or EA for different periods of time. The surface protein and mRNA expression of ICAM-1 and VCAM-1 were determined by flow cytometry and real time RT-PCR, respectively. Adhesion of leukocytes to TFA-treated HAECs was evaluated by an adhesion assay. Activation of nuclear factor-B (NF-B) was evaluated by measuring NF-B p65 phosphorylation using flow cytometry. ROS production was determined by the reduction of fluorescent 2',7'-dichlorofluorescein diacetate (DCFH-DA). LA treatment significantly increased protein and mRNA levels of ICAM-1 and VCAM-1, leukocyte adhesion to HAECs, phosphorylation of NF-B and ROS generation. Similar effects were achieved for cells incubated with EA. Experiments with HAECs pretreated with pyrrolidine dithiocarbamate, an inhibitor of NF-B, revealed that both LA and EA-mediated induction of ICAM-1 and VCAM-1 is mainly regulated by NF-B. The ROS production induced by both of the studied acids was inhibited in the presence of diphenyleneiodonium (DPI), a NADPH oxidase inhibitor, suggesting ROS production through the activation of NADPH oxidase. Furthermore, LA or EA-induced ICAM-1 and VCAM-1 expression, activation of NF-B and adhesion of leukocytes to HAECs were abolished in the presence of DPI. Conclusion: TFAs present in our diet have a direct proinflammatory effect, which promotes leukocyte adhesion to the endothelium through ROS-dependent NF-B activation.
The fatty acid composition of milk from Lowland Black-and-White and Polish Red cows was determined for the period of pasture feeding. The total fatty acid profile was determined by gas chromatography with a 50 m long polar capillary CP Sil 88 column. The content of trans C18:1 acid was determined with the same column after separating first the fraction of trans monoenoic methyl esters by silver-ion thin-layer chromatography. The milk fat from Lowland Black-and-White cows was found to have significantly higher proportion of long-chain saturated fatty acids as compared with milk fat from Polish Red cows for the same feeding conditions. The proportion of monoenoic acids, including the isomers of trans-18:1 acid and polyenoic acids, was significantly higher in milk fat from Polish Red cows than Lowland Black-and-White cows.
This review comprises the impact of trans fatty acids (tFA) and conjugated linoleic acids (CLA) in the human nutrition. The knowledge of the impact of the relation between dietary tFA and the risk of cardiovascular diseases diabetes mellitus type-2, and cancer increased in the last years. There is increasing evidence that the effects of tFA on human health differ among positional trans-isomers. CLA show various metabolic properties mainly anti-cancerogenic, anti-inflammatory, and antiatherogenic, with potent impact in humans.
This review summarizes the up-to-date data on the consumption pattern of trans fatty acids in different countries including Poland, as well as the metabolism and metabolic effects of trans fatty acids in human organism. The health hazards linked with the consumption of trans fatty acids are also discussed.
The results of several studies indicate that consumption of trans fatty acids increases plasma LDL-cholesterol and plasma lipoprotein (a) levels, two independent biochemical risk factors for the development of coronary heart disease. With regard to the harmful effect of trans fatty acids on human health and the lack of randomized studies in Poland on their content in food, the monitoring study was started. The fatty acid composition of 107 randomly selected products from 7 food groups in the whole country was analyzed by high-resolution capillary gas chromatography. The highest content of trans fatty acids was detected in the group of dry soups and sauces (18.86%) followed by confectionery (10.14%) and chocolate products (7.86%), than snacks and potato chips, fast foods and hard and soft margarines in decreasing order.
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