Fatty acids are the basic units of fat composed of hydrocarbon chains with a carboxyl group at one end. They can be saturated, containing only single bonds between carbon atoms, or unsaturated with one or more double bonds. Saturated fatty acids are solid at room temperature due to close packing, while unsaturated fatty acids are usually liquid due to kinks in their structure. Fatty acids are produced via hydrolysis of triglycerides from plants and animals, which involves splitting the triglyceride into glycerol and three fatty acid molecules. The fatty acids can then be purified by distillation and fractionation.

2. Chapter 4: Fatty Acid
4.1 Composition/Production of fatty acids and its
derivatives.
4.2 Flow chart
4.3 Uses and application of fatty acids.

4. Fatty acids:
• basic units of fat composed of chains of carbon
atoms
• an acid group at one end and hydrogen atoms
attached all along their length

5. Fatty Acids
 The simplest lipids are the fatty acids, which rarely exist alone in nature, but
instead are usually a component of more complex lipids
 Fatty acids are carboxylic acids with a long hydrocarbon chain attached
 Although the acid end is polar, the nonpolar hydrocarbon tail makes fatty acids
insoluble (or sparingly soluble) in water

6. Structure of fatty acids
• A fatty acid consists of a hydrophobic hydrocarbon
chain with a terminal carboxyl group

7. Triacylglycerols
 Triacylglycerols (also called triglycerides) are tri-fatty acid esters of glycerol
 Triacylglycerols are the major form of fatty acid storage in plants and animals
 Triacylglycerols can be classified as fats or oils
- fats are solid at room temperature and most come from animals
- oils are usually liquid at room temperature and come from plants (palm and
coconut oils are solids at room temperature)

8. Lipids
 Lipids are diverse in form and are defined by solubility in non-polar
solvents (and insolubility in water)
 Lipids are used for efficient energy storage, as structural components of cell
membranes, as chemical messengers and as fat-soluble vitamins with a
variety of functions
 We consume many lipids from a variety of plant and animal sources
 Types of lipids include fatty acids, prostaglandins, waxes, triacylglycerols,
glycerophospholipids, sphingolipids, glycosphingolipids and steroids
(cholesterol, bile salts and steroid hormones)

9. Types of Lipids
• Lipids with fatty acids
Waxes
Fats and oils (trigycerides)
Phospholipids
Sphingolipids
• Lipids without fatty acids
Steroids

11. Classification of fatty acids
Fatty
acids
saturated unsaturated
monounsaturated polyunsaturated

12.  Fats that are solid at room temperature
are made up mainly of saturated fatty
acids.
 Fats that are liquid at room temperature
are made up mainly of unsaturated fatty
acids.

13. Saturated Fatty Acids
 Appear to raise the level of LDL (“bad”)
cholesterol in the bloodstream
 Food sources: meat, poultry skin, whole-
milk dairy products, and the tropical oils-
coconut oil, palm oil, and palm kernel oil.

14. Polyunsaturated Fatty Acids
 Fats that seem to lower total
cholesterol levels.
 Food sources: many vegetable oils,
such as corn oil, soybean oil and
safflower oil.

15. Corn oil contains 86% polyunsaturated fatty acids
Therefore is a liquid at room temperature.
Olive oil contains monounsaturated fatty acids.
Therefore is a liquid at room temperature, likely to
solidify when refrigerated.
Saturated fatty acids (tropical oils, animal fats) are
solids, or nearly solids at room temperature.

16. Physical Properties of Saturated Fatty Acids
Saturated fatty acids have:
 Molecules that fit closely together in a
regular pattern
 Strong attractions (dispersion forces)
between fatty acid chains
 High melting points that makes them
solids at room temperature.

17. Structures and Melting Points of Saturated Fatty Acids

18. Physical Properties of Unsaturated Fatty Acids
Unsaturated fatty acids have:
 Nonlinear chains that do not allow molecules to pack closely
 Weak attractions (dispersion forces) between fatty acid chains
 Low melting points and so are liquids at room
temperature

19. Structures and Melting Points of Unsaturated Fatty Acids

21. • Triglycerides are the main constituents of
natural fats and oils.
• A triglyceride (triacylglycerol ) is an ester
formed from glycerol and three fatty acid
groups.

27. Batch Process
- Twitchell : used catalst
Continous Process
- Colgate-Emery Process : Higher T & P
Enzymatic Process
- Eg. Lipases
Method of
Fatty Acids
Splitting

28. Hydrolysis of Fats and Oils
 Fats and oils contain ester groups which can be hydrolyzed with aqueous
acid, aqueous base (saponification) or enzymes
 The hydrolysis products are glycerol and three fatty acids

29. Fat splitting is homogeneous reaction that proceeds in stage
The fatty acid radical displace from triglyceride one at a time
from tri to di to mono.
Fat splitting is reversible reaction, at point of equilibrium
Increase in temperature (from 150°c to 220°)and pressure
enhance the solubility Of oils in water by two to three times.
Chemical reaction in hydrolyser:
(R-COO)3C3H5 + 3H2O ↔ 3R.COO.H + C3H5(OH)3
Tri-glyceride + water ↔ fatty acid + glycerine

30. Process of Fat Splitting :
• The single stage counter current splitting process in a
tower is particularly suited for the handling of larger feed rates.
• It operates continuously, permitting maximum heat recovery.
• The splitting temperature of 245-255 deg C ensures
adequate dissolving of aqueous phase in the fat so that
physical agitation is not required.

31.  The crude fat pass through the tower from bottom to
top as a coherent phase, while the heavy splitting water
travels down wards as a dispersed phase through the
mixture of fat and fatty acid.
 Splitting efficiency of 99% and above are reached
consistently.

32. SINGLE STAGE COUNTERCURRENT SPLITTING

35. Fatty Acid Process
Distillation
Fractionation
Hydrogenation

36. Distillation Process
 Fatty acid produced from various fats splitting's process are purified
by distillation and can also be separated into individual fatty- Acids
by fractional distillation.
 Fatty acids are very sensitive to heat, oxidation & corrosion effects
due to the presence of acid group so material of construction is very
important.

37. FATTY ACID DISTILLATION
Process Principle
:
The fatty acid is
evaporated under
vacuum
(occasionally with
the addition of live
steam for fatty
acid circulation
and partial
pressure
reduction).

39. Fractional Distillation
Why?
 Crude FA contain unsaponifiable matters, dark color, polymeried FA
 To separate different type of FA (saturated and unsaturated)
 Remove impurities and color
How?
 Different number of carbon has different boiling point
 Carry out under high vacuum and low temperature

40. Fractionation Process
 The Fatty Acid Fractionation process separates the Fatty Acid into much
narrower components to obtain fractional purities of up to 99.5% for products
like Fatty Alcohols, Methyl Esters of Fatty Acids and other organic compounds.
 The design process employed optimizes the recovery of heat and provides the
highest quality of product available in the market today.
 Vacuum towers equipped with structured packing are utilized to fractionate
the fatty acids.
 While the vapors are condensed on the surface condensers, the reflux is
evaporated by the Falling Film Evaporators.

41. Fractional Distillation
Fatty Acid Fractionation :
 Fractionation makes it possible to
separate the fatty acid mixture in to
narrower cuts or individual
component.
 Detergent grade feed stock C12-C18 is
separated from the whole cut by
topping off the C8-C10 fraction.
 The middle cut, C12-C14, can be
further fractionated from the C12-C18
through the multistage Fractionation
by employing two or more columns.
 Vacuum system is provide
Independently for each column to
achieve highest vacuum and greater
recovery of desired products.

43. Cis and Trans Unsaturated Fatty Acids
 Natural unsaturated fatty acids have cis double bonds
 When unsaturated vegetable oils are hydrogenated to form more saturated
oils (as in margarine), some of the cis fatty acids are isomerized to trans fatty
acids
 Trans fatty acids are much more linear than cis fatty acids, so their melting
points are higher and studies have shown that trans fats may act similarly to
saturated fats and could contribute to heart disease and some cancers
 Due to new requirements for including amounts of trans fats on food labels,
many companies are developing hydrogenation methods that do not produce
trans fats

45. Product of Hydrogenation
Hydrogenation converts double bonds in oils to single bonds. The solid
products are used to make margarine and other hydrogenated items.

46. Hydrogenation
 To saturated the double bonds of fatty acid
 Usually saturated FA is more favorable compare to unsaturated FA

47. FATTY ACID HYDROGENATION

48. Hydrogenation of Unsaturated Oils
 Hydrogenation converts alkenes to alkanes
 So, hydrogenation of unsaturated oils produces saturated fats
 Hydrogenation is typically carried out by bubbling H2 gas through the heated
oil, in the presence of a metal catalyst (such as nickel or platinum)
 Unsaturated oils are usually only partially hydrogenated, so that the product is
not completely saturated, giving a soft semisolid fat such as margarine
Pt
CH2 O C
O
(CH2)16CH3
CH2 O C
O
(CH2)16CH3
CH O C
O
(CH2)16CH3
+3H2
CH
CH2
O C
O
(CH2)7CH CH(CH2)7CH3
O C
O
(CH2)7CH CH(CH2)7CH3
CH2 O C
O
(CH2)7CH CH(CH2)7CH3