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Hydrogenation & Trans Fats. Hydrogenation & Trans Fats. When naturally occurring unsaturated fatty acids are altered by partial hydrogenation, they are converted to saturated fatty acids, which have the effect of straightening the chains and changing the physical properties.
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Hydrogenation & Trans Fats • When naturally occurring unsaturated fatty acids are altered by partial hydrogenation, they are converted to saturated fatty acids, which have the effect of straightening the chains and changing the physical properties. • Also during partial hydrogenation, some of the unsaturated fatty acids, which are normally found as the cis isomer about the double bonds, are changed to a trans double bond and remain unsaturated. • Trans fatty acids of the same length and weight as the original cis fatty acids, still have the same number of carbons, hydrogens, and oxygens but they are now shaped in a more linear form, as opposed to the bent forms of the cis isomers.
The Process • A metal catalyst such as nickel, zinc, copper, or other reactive metals is used to react with the hydrogen gas which is bubbled up through the mixture. The metals catalyze the hydrogen and carbon atoms and converts the fatty acids by flipping one of the attached hydrogen molecules and rotating it half the diameter of the carbon chain. • This effectively creates a new molecular shape resulting in a stiffer or more rigid material, hence the change from a liquid to a semi-solid or solid substance.
Making Margarine • Vegetable oils are commonly referred to as "polyunsaturated". • Vegetable oils may be converted from liquids to solids by the hydrogenation reaction. • Margarines and shortenings are "hardened" in this way to make them solid or semi-solids. • Vegetable oils which have been partially hydrogenated, are now partially saturated so the melting point increases to the point where a solid is present at room temperature. • The degree of hydrogenation of unsaturated oils controls the final consistency of the product.
Info on Trans Fats • Trans fats are banned in NYC • Estimated average consumption of trans fatty acids is 3-4% of daily energy intake in the United States Journal of Lipid Research 2008 • Among other results, researchers have found that trans fatty acids significantly raise LDL cholesterol levels, the bad cholesterol, while lowering the HDL levels, the good cholesterol. • Trans fats are associated with increased inflammation in the arteries. • Trans fats have been found to change the composition of cell membranes, making them more leaky to calcium. • Inflammation, high LDL cholesterol and calcified arteries are the signature ingredients of atherosclerosis.
Info on Trans Fats • Interfere with an enzyme that converts the essential fatty acid linoleic acid into arachidonic acid, which is needed for the production of prostacyclin (a blood-flow enhancer) and thromboxane (which regulates the formation of blood clots needed for wound healing). • Can cause sudden blood clots or stop of blood flow, resulting in cardiac arrest.
Hydrogenation – adding hydrogen to unsaturated fatty acids (oils) Unsaturated oils (1) Saturated fats (intended product) AND (2) harmful byproduct of process trans fats (unsaturated trans- conformation fatty acids)