Chemistry of Fats Oils and Waxes PDF
Chemistry of Fats Oils and Waxes PDF
Chemistry of Fats Oils and Waxes PDF
and Waxes
Centeno, Kathryn
Lipids
Lipids are a class of biological molecules
defined by low solubility in water and high
solubility in nonpolar solvents.
Role of Lipids
1. They store energy and protect and insulate internal
organs. In human bodies they are stored as fat
cells and in animal bodies as starch.
2. They are found in nerve fibers and hormones as
steroids, which act as chemical messengers.
3. Because they are not soluble in water, a major
function of lipids is to build the cell membranes that
separate the internal contents of cells from the
surrounding aqueous environment.
Classification of Lipids
1. Triglycerides
- derived from glycerol and three fatty acids
2. Phospholipids
- contains glycerol and two fatty acids
3. Steroid
- composed of four fused rings of carbon where
functional groups are attached
4. Waxes
-organic compounds that characteristically
consist of long alkyl chains.
Fatty Acids
A fatty acid contains a long chain
attached to carboxylic acid
group at one end.
Normally, fatty acid contains an
even number of carbon atoms,
usually between 12 and 20.
They are insoluble in water
because the size of the
nonpolar portion is bigger than
the size of polar portion
(carboxyl group). They form
micelle in water.
a. Cis Unsaturated Fat - H atoms on the same side of the double bond. have lower
melting points than trans fats since this configuration causes more kinking of the chain.
The molecules are not as closely packed, decreasing the strength of the van der Waals
forces between them.
b. Trans Fat - H atoms on opposite sides of the C=C double bond. Occurs in processed
unsaturated fats commonly through hydrogenation process
Fats
Oils
Generally liquids at room temperature.
Contains more unsaturated fatty acids. The double
bond in unsaturated fatty acids produces a kink in
the chain which means that the fat molecules can not
pack closely together. As the number of C=C
double bonds increases the amount of kinking
increases and the distance between the fat
molecules increases. This decreases the strength of
the Van der Waals forces between the molecules,
decreasing the melting point.
Waxes
The word "wax" is derived from the old
English "weax" for the honeycomb of the
bee-hive. Thus, bee wax can be
considered as the reference wax.
Wax is the water resistant protective
coatings of leaves, fruits, and trees,
also in animals, algae, fungi and bacteria.
Wax is hydrophobic in nature produced by
combining fatty acids with alcohols.
All waxes are water-resistant materials made up of various substances includinghydrocarbons
(normal or branched alkanes and alkenes), ketones, diketones, primary and secondary alcohols,
aldehydes, sterol esters, alkanoic acids,terpenes (squalene) and monoesters (wax esters), all with
long or very long carbon chains (from 12 up to about 38 carbon atoms) and solid in a large range
of temperature (fusion point between 60 and 100C).
They are soluble in aromatic solvents, chloroform, ethers, esters and ketones.
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Essential Fats
1.
Omega 3 Fats
Once eaten, the body converts (alphalinolenic
acid) ALA to (eicosapentaenoic acid ) EPA and
(docosahexaenoic acid) DHA, the two types of
omega-3 fatty acids more readily used by the
body.
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Sources
Essential Fats
2. Omega 6 Fats
Linoleic acid is converted in the body to the longchain polyunsaturated fatty acids gamma-linolenic
acid (GLA) and arachidonic acid (AA)
Sources
2016-8-13
Health Benefits
Deficiency
Abnormalities in the liver and kidney
Changes in the blood
Reduced growth rates
Decreased immune function
Depression
Skin changes, including dryness and scaliness, Eczema
Mental disorders
Diabetes
Atherosclerosis
Hypertension, PMS, and inflammatory conditions such as
rheumatoid arthritis.
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