Hydrogenation & Trans Fats. When naturally occurring unsaturated fatty acids are altered by partial...
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Hydrogenation & Trans Fats. When naturally occurring unsaturated fatty acids are altered by partial hydrogenation, they are converted to saturated fatty
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.
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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.
Slide 6
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.
Slide 7
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.
Slide 8
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.
Slide 9
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)
