For presentation purpose. Presenter, Brenda Chong. Fats and oils reactions.

1. OILS AND FATS

2. FATS AND OILS
95–99%
1–4%
GLYCEROL
DERIAVATIVES
•Glycerol
•Free fatty acids
•etc.
Triglycerides
NON
GLYCEROL
DERIAVATIVES
•Phospholipids
•Sterols
•Pigments
•Hydrocarbons
•Antioxidants
•Etc.

3. Fat
• Solid in room
temperature.
• A ester of fatty acids
and saturated
hydrocarbon chains.
Oil
• Liquid in room
temperature.
• A ester of fatty acids
and unsaturated
hydrocarbon chains.
All oils are fats,
but not all fats are oils.

4. HYDROGENATIONS
Hydrogenation converts double bonds
in oils to single bonds (Unsaturated to
saturated).
The solid products of hydrogenations
from oil are used to make margarine
and other hydrogenated items

5. Hydrogenation is a process by which hydrogen is added
directly to points of unsaturation in the fatty acids.
In the process of hydrogenation, hydrogen gas is reacted
with oil at elevated temperature and pressure in the
presence of a catalyst.
The catalyst most widely used is nickel.

6. HYDROLYSIS
Triglycerides will be hydrolyzed and split into
glycerol and 3 fatty acid.
The resulting alkaline salts of fatty acids (soaps)
and the process is saponification (hydrolytic of
cleavage fats)
TRIGLCERIDE
S
GLCEROL + 3 FATTY ACIDS
ALKALI (NaOH/KOH)

7. When the triglycerides is treated with NaOH (Base), glycerol and
sodium palmitate (soaps) will be formed through the hydrolysis with
a strong base. Eg, KOH.
Triglycerides split into glycerol and the salts of fatty acids (soaps).
The process of the formation of sodium palmitate is called
saponification.
**Stronger base gives softer soaps.

8. Fat metabolism:
DEGRADATION
Degradation of fats in adipose tissue
Adipose tissues = fat cells = fat storage
Degradation of Triacylglycerols TAG (fats)in adipose tissue (lipolysis) is
catalyzed by hormone sensitive lipase (HSL).
This enzyme is activated by epinephrine and glucagon and inhibited by insulin.
http://web.indstate.edu/thcme/mwking/fatty-acid-oxidation.html

9. Utilization of Fatty Acids
for ENERGY
 Triglycerols are degraded to
fatty acids and glycerol in the
adipose tissue and
transported to other tissues.
Eg, liver cells and
mitochondrial matrix.
 Fatty acids are activated and
transported into the
mitochondria.
 Fatty acids are broken down
into two-carbon acetyl–CoA
units and fed into the citric
acid cycle.

10. AUTO OXIDATION
& RANCIDITY
Oxidative rancidity or auto oxidation is the chemical
decomposition of fatty acids which produces unpleasant
odors and taste.
Fatty acids further undergo auto-oxidation and is broken
down to hydrocarbons, aldehydes, ketones and small
amount of alchohol and epoxides.

11.  This process is the production of free radicals in a catalytic chain reaction.
 This process can go virtually forever. (continuous on and on)
 i.e. The ether radical can react with atmospheric oxygen (O2) to form
an alkylperoxy radical, which in turn can react with a second molecule of ether to
form a hydroperoxide and generate an ether radical identical to the one we started
with. This new radical can also react with oxygen to form additional hydroperoxide
and generate an identical radical.
Auti-oxidation /
(Catalytic chain
reaction)

12.  An ether group is an oxygen connected to 2 alkyl group .
General formula : R-O-R
 i.e. The ether radical can react with atmospheric O2 to form
an alkylperoxy radical, which in turn can react with a second molecule of
ether to form a hydroperoxide and generate an ether radical identical to the
initial one.
 And the process of producing new radical will go on and go on. (non-stop)

13. 1. To remove auto oxidation and rancidity, fatty
acids are often treated with citric acid.
2. Also, antioxidants are often added to fat-
containing foods in order to retard the
development of rancidity due to oxidation.
3. Eg. Natural anti-oxidants include flavonoids,
polyphenols, ascorbic acid (vitamin C) and
tocopherols (vitamin E).

14. CHYLOMICRONS
 Chylomicrons are compounds which are triglycerides
coated with protein and cholestrol.
 Chylomicrons is a one of the type of lipoprotein.
 Lipoproteins help in the movement of fats and
cholestrol in the blood stream.

15. Lipoproteins
● Chylomicrons
carry TAG (fat) from the intestine to the
liver and adipose tissue
● VLDL – VERY LOW DENSITY LIPOPROTEIN
carry (newly synthesized) TAG from the liver
to peripheral tissues
● IDL – INTERMEDIATE DENSITY
LIPOPROTEIN
are intermediate between VLDL and LDL
● LDL – LOW DENSITY LIPOPROTEIN
carry cholesterol from the liver to cells of
the body
● HDL – HIGH DENSITY LIPOPROTEIN
collects cholesterol from body´s tissues and
brings it back to the liver
Figure was assumed from
http://http://www.britannica.com/EBchecked/topicart/720793/92254/Cutaway-view-of-a-low-density-lipoprotein-complex-The-LDL