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Fats, Oils and Detergents

By : Shriya Tiwari

Fats, Oils and Detergents

Fats, Oils and Detergents
Fats and Oils
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Natural fats
Edible and industrial oils of vegetable
origin
Glycerides
Common fatty acids
Physical properties
Chemical properties :
Hydrolysis(Saponification)
Hydrogenation

Important Chemical Constants
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Acid value
Saponification value
Iodine value
Soaps and Detergents

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1)
2)

Soaps
Synthetic detergents
Typical synthetic detergents
Alkyl sulphonates
Aryl sulphonates

Fats and Oils

Fats and Oils

Chemically, they are esters of higher
aliphatic monocarboxylic acids with
glycerol and are :- also called
triacylygylcerols(triglycerides/glyc
erides)
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Fats and oils are also known as
lipids , i
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Fats and Oils

Occurrence
1)

Natural Fats

Obtained from animal sources such
as (a) butter (from milk of cows and
Buffaloes) , (b) tallow(from sheep,
goats etc), (c) lard(from pigs)
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3) Industrial oills of vegetable origin:
Used in industries such asSoap, paints, varnishes, lacquers

Structure
Fats and oils are triesters of glycerol with long chain carboxylic acids
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Physical
Properties

2
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They are largely soluble in
organic solvents (benzene,
chloroform and petroleum
ether)
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p
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p
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Hydrolysis in presence of
steam or mineral acids
provides

a mixture of free fatty acids and
glycerol
...
Since, the salts of fatty
acids thus formed are used as
soap, alkaline hydrolysis is

commonly known as
saponification
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Chemical
properties
● Hydrogenation

Oils containing a large proportion of
unsaturated acid part in their
glycerides add on hydrogen
(becomes saturated) in presence of
finally divided nickel and change
into solid fats
...

Hydrogenation is used
commercially in the manufacturing

Chemical
properties
● Hydrogenation

of vegetable ghee from cotton
seed, coconut, groundnut or pea nut
oils
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Acid value

It is determined by dissolving a
known quantity qof fats or oils in
pure alcohol and titrating against
standard KOH solution using
phenolphthalein as indicator
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Saponification
value

The number of mg of KOH required
to completely sponify 1g of fat/oil
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Smaller the saponification value,
higher the molecular weight
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Iodine value

It is the measure of the extent of
unsaturation in fat/oil and gives an
idea of its “drying” character
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Soaps and
Detergents

Soaps

Definition:-Soaps are organic
compounds obtained from natural
fats or oils which are used as
cleaning agents for various
purposes
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It is obtained by hydrolysis of
oils and fats by sodium hydroxide
(saponification)
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Synthetic
detergents

Unlike soaps, detergents can be
used even in hard water since they
do not form curd like ppts
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Typical synthetic detergents
Alkyl sulphates
They consists of sodium alkyl sulphates
obtained from long chain alcohols

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