Fats and oils are triglycerides composed of fatty acids esterified to glycerol. They can be classified as simple or mixed depending on the fatty acid composition. The main difference between fats and oils is their melting point, with fats being solid at room temperature and oils being liquid. Fats and oils undergo various chemical reactions including saponification, hydrogenation, and oxidation. Analytical tests such as acid value, saponification value, and iodine value provide information about fatty acid composition and purity. Fats and oils have many uses including in soaps, foods, and lubricants.

1. Fats and oils

2. ROLL NO. NAME TOPICS COVERED
57 MALI DISHA INTRODUCTION
58
59
MARDA SIDDESH
MATALE SHRUTIKA
CHEMIICAL REACTION
61 MOGAL ANUJA SAPONIFICATION
RANCIDITY
62 MOKAL ANKITA DRYING
ACID VALUE
SAPONIFICATION VALUE
63 MORE DIVYA ESTER VALUE
IODINE VALUE
ACETYL VALUE
64 MULE TEJAS RM VALUE
USES

3. Introduction
 Fats and oils are the major part of the lipid present in
the adipose tissue of mammals.
 Fats and oils are the esters of fatty acids and alcohols
and on hydrolysis gives fatty acids and alcohols.
 Fats and oils are mainly the glyceryl esters of various
fatty acids like palmitic, stearic, oleic, linoleic and
linolenic. These are also called as triglycerides.

4. Fats and oils are of two types
a) Simple- When the three fatty acids of triglyceride are
same.
b) Mixed- When the three fatty acids of trigylceride are not
identical.
 Natural fats are mainly mixed glycerides and they do not
have free acid or base (groups) so also known as neutral
fats. Fats and oils are obtained from plants as well as
from animals.
 A crude fat along with the glyceryl ester contains some
amount of free fatty acids and 1-2% of unsaponifiable
matter like sterols.

5.  Difference between fats and oils.
FATS OILS
SOLID OR SEMISOLID AT ROOM
TEMPERATURE
LIQUID AT ROOM TEMPERATURE
CONTAIN LARGE AMOUNT OF
SATURATED FATTY ACIDS
CONTAIN LARGE AMOUNT OF
UNSATURATED ACID
HIGH MELTING POINT LOW MELTING POINT
FATS ARE ANIMAL FATS OILS HAVE VEGETABLE FATS
FATS DO NOT CONTAIN DOUBLE
BONDS
OILS HAVE DOUBLE BOND
FATS ARE MORE STABLE OILS ARE LESS STABLE
Physical and Chemical Properties of Fats:
Fat and oils are colourless or pale yellow in colour. These
are insoluble in water and polar solvents but soluble in
non-polar solvents such as ether, carbon tetrachloride and
carbon disulphide

6. SIMPLE
MIXED

7. Basic concepts in salt formation
Salts are formed when a compound that is ionized in solution forms
a strong ionic interaction with an oppositely charged counterion,
leading to crystallization of the salt form
In the aqueous or organic phase, the drug and counterion are
ionized according to the dielectric constant of the liquid medium.
The charged groups in the drug's structure and the counterion are
attracted by an intermolecular coulombic force.
During favorable conditions, this force crystallizes the salt form.
All acidic and basic compounds can participate in salt formation
However, the success and stability of salt formation depends upon
the relative strength of the acid or base or the acidity or basicity
constants of the species involved

8. The salt form is separated into individual entities (i.e., the
ionized drug and the counterion) in liquid medium, and its
solubility depends upon the solvation energy in the solvent.
The solvent must overcome the crystal lattice energy of the
solid salt and create space for the solute.
Thus, the solubility of a salt depends on its polarity,
lipophilicity, ionization potential, and size.
A salt's solubility also depends on the properties of solvent
and solid such as the crystal packing and presence of solvates

9. Formation of halides
A halide is a binary phase, of which one part is a halogen atom and
the other part is an element or radical that is less electronegative (or
more electropositive) than the halogen, to make a, e.g., fluoride,
chloride, or theoretically tennesside compound.
The alkali metals combine directly with halogens under appropriate
conditions forming halides of the general formula, MX (X = F, Cl, Br or
I). Many salts are halides; the hal- syllable in halide and halite reflects
this correlation.
All Group 1 metals form halides that are white solids at room
temperature.
A halide ion is a halogen atom bearing a negative charge. The halide
anions are fluoride (F), chloride (CI), bromide (Br), iodide (1) and
astatide (At). Such ions are present in all ionic halide salts. Halide
minerals contain halides.All these halides are colourless, high melting
crystalline solids having high negative enthalpies of formation.

10. Formation of esters:
Fatty acids reacts with alcohol in the presence of a strong
acid to form ester(triglycerides)
3 H3-(CH2)14-C=O + CH2OH -H2O CH2O CO(CH2)14CH3
HC O CO(CH2)14CH3
H2C OH H2C O CO(CH2)14CH3
Palmitic acid Glycerol Palm Oil
OH
HC OH

11. Reduction or hydrogenation:
 Unsaturated fatty acid undergoes reduction or hydrogenation in
presence of reducing agents to form saturated fatty acid.
OH
3HC-(CH₂)7-CH=CH-(CH₂)7-C=O
Oleic acid
H2
Ni
OH
3HC-(CH2)7-CH2-CH2-(CH2)7-C=O
Stearic acid

12. Saponification
 The alkaline hydrolysis of oil or fat (Glyceride) to form Soap (Alkali
Salt of higher fatty Acid & glycerol is known as saponification.
 Reaction- Triglycerides are generally animal fats & Vegetable oils.
When they are, reacted with Sodium hydroxide, a hard form of soap
is created.
Ester + Base Alcohol + Soap

13. Rancidity of oils
 Rancidity is the complete or in complete oxidation or hydrolysis of
fats and oils when exposed to air, light, moisture or by bacterial
action, resulting in unpleasant taste & odour.
Types of Rancidity:
Hydrolytic Rancidity:- In case of fats of oil the hydrolytic reaction
will occur at the point where the fatty acids are connected to glycerol in
triglyceride molecule.In fatty acids gets Split off from glylen forming a
free fatty acids.

14. How to prevent Rancidity?
 To keep them away from direct sunlight or air.
 To keep them in Refrigerator
 Adding antioxidants.

15. Drying of oils
When highly unsaturated oils are exposed to air, they
undergo oxidation and polymerization to form a thin
waterproof film. such oils are called Drying Oils and the
reaction is referred to as drying
Linseed oil which is rich in linolenic acid is a common drying
oil used in oil based paints

16. Analytical Constants
Acid Value:
It is defined as the number of mg of koH required to completely
neutralize Free fatty acids present in one gram of fat or oil.
It is a measure of the free fatty acids present fat or oil
Principle:
It is determined by by titrating the sample of oil or fat in
alcoholic medium F against 0.1 M KOH
Formula:
Acid value= 5.61 n/w
Where n = burette reading
W = sample weight

17. Significance
Measure of acids breakdown of triglycerides into free.
Fatty acids which has an adverse & undesirable effect
Measure of degree of hydrolytic rancidity.

18. Saponification Value
Saponification number is defined as the number of milligrams of
KOH required to saponify one gram of Fat and oil
Principle
Saponification is the process by which the fatty aids in the
triglycerides or fat are hydrolyzed by an alkali to give glycerol
and potassium salts of fatty acids.
A known quantity of fat or oil is refluxed with an excess
amount of alcoholic KOH.
After saponification the remaining KOH is estimated by
titrating it against a standard acid.
The value obtained is used for the determination of
saponification no of fats and oil

19. Sample is titrated with with 0.5M HCI ( back reading, a ml).
Perform blank titration (b ml)
Saponification value = 28.05(b-a)/w
Significance
Gives an idea about the molecular weight of fat/ oil. smaller
the saponification value higher the molecular weight
Indicates the amount of alkali required for converting oil / fat
into soap
It also indicates the length of carbon chain of the acid present
in that particular oil chain or fat.

20. Ester Value:
It is the number of mg of KOH required to saponify the ester
present in 1gm of the substances.
Ester value = Saponification value - Arid Value
Reaction:

21. Principle:
It is determined by titrating the Sample of sil & fat in alcoholic
medium against 0.5m Hcl.
Formula:
E.V=S.V-A.V
Significance:
The ester value shows the amount alkali consumed in the
saponification of the ester and if possible identify and diffrentiate
the fats with this value

22. Iodine Value:
It is the number of grams of iodine that would add to C=C present
in 100 g of the fats and ail.
Reaction:

23. Principle:
The oil / fat sample taken in Carbon tetrachloride is treated
with a known excess of iodine monochloride Solution in glacial
acetic acid.
 The excess of jodine monochloride is treated with
potassium lodide.
Now, this sample is titrated against 0.1M Sodium
thiosulphate solution, starch solution used as a indicator for
estimation of liberated iodine (A) and then perform blank
titration (B)
Iodine value =1.269(b-a)/w
Formula:

24. Significance:
The lodine value is a measure of the amount of double bonds
(unsaturation) in a fats.
Iodine Value = No. of double bond ↑
Unsaturated Lipids are more susceptible to rancidity

25. Acetyl value:
It is the mg of KOH required to acetic acid liberated by the hydrolysis of
1g of the acetylated Substance
Principle:
It is determined through saponification value
The process consists of acetylating the oil with a measured
quantity of acetic anhydride in pyridine decomposing the excess
anhydride by boiling with water and then addition in of sufficient
butyl alcohol to give a homogenous solution titrating with alkali.

26. Significance:
It is the measure of hydroxy OH acids in lipids
Acetyl value = more amount of free fatty acids
Formula:
Acetyl value= 1335(b-a)/(1335-a)
Where,
a= saponification of the substance
b= saponification value of the acetylite substance

27.  Reichert-Meissl number [Reichert Meiss (RM) value]
 It is defined as the ml of 0.1 N KOH required to neutralize the
soluble volatile fatty acids distilled from 5 g fat.
 RM number is useful in testing the purity of butter since it
contains a good concentration of volatile fatty acids (butyric
acid, caproic acid and caprylic acid).
 Butter has a RM number in the range 25-30, while it is less than
I for most other edible oils. Thus any adulteration of butter can
be easily tested by this sensitive RM number.
Reichert Meissl RM value

28. Principle:
 Fat is saponified using glycerol-alkali solution & acidified by
sulphuric acid to liberate free fatty acids.
 The liberated fatty acids are steam distilled and the steam
volatile fatty acids are collected (as condensate). The cooled
condensate of the volatile fatty acids is filtered for separation of
water soluble and water insoluble fatty acids.
 The water soluble fatty acids is titrated with alkali to give RM
value.
 Water-insoluble fatty acids is titrated to give the polenske value.

29. Significance:
 It is a measure of water soluble steam volatile fatty
acids chiefly butyric and caproic acids present in oil
or fat.
 No other fat contains butyric acid glycerides, and
therefore, the Reichert Meissl value of the butter
fat is higher than that for any other fat.
 These determinations have been used principally
for analysis of butter and margarines.

30. USES OF FATS AND OILS :
(1)They are energy reservoirs and are more efficient proteins and
carbohydrates.
(2) They are used in soap industries.
(3) They are used as raw materials for preparing higher alcohols used for
manufacturing synthetic detergent.
(4) Groundnut oils are used for manufacturing Vanaspati ghee
(marketed as Dalda, Rath, Gagan, etc.).
(5) Castor and cotton seed oils are used as purgatives.
(6) Cod liver oils are used in vitamin A and D deficiency conditions.
(7) They provides excellent insulation since fat is bad conductor of heat.
(8) Derived lipids are important building blocks of biologically active
materials.