INTERESTERIFICATION

1
INTERESTERIFICATION
2
Interesterification
Interesterification involves an exchange of acyl
group among triglycerides. Acyl groups may
exchange positions within a triglyceride or among
triglyceride molecules.
3
Interesterification
4
Probablity of Different Triglycerides Formation
If A, B, and C are the molar percentages of fatty
acids A, B, and C for a commercial oil, Then,
molar percentage of glycerides containing only 1
acid is AAA A3 10,000 Molar percentage
of glycerides containing 2 acids is AAB
3A2B 10,000 And molar percentage of glycerides
containing 3 acids is ABC 6ABC 10,000
5
Intraesterification, Interesterification and
Equilibrium Mixture.
S
O
L
Catalyst
O
O
L
L
S
O
S
L
S
Continued reaction

S
S
S
S
S
S
O
L
S
L
S
S
S
S
S
O
O
L


L
O
L
O
L
O
S
S
S
L
O
L
O
O
O
O
L
L
O
O

L
L
L
L
O
O
L

(SUS
SSU) (SUU
USU)
UUU
SSS





6
Random Interesterification
A. S (Stearic acid 35)
B. S (50)
O (Oleic acid 30)
O (40)
L (Linoleic acid 35)
L (10)
After random interesterification, the
triglyceride compositions are
Sample A
Sample B
Triglyceride

Triglyceride

SSS
4.3
SSS
12.5
OOO
2.1
OOO
6.4
LLL
4.3
LLL
0.1
SSO
11.0
SSO
30.0
SSL
12.8
SSL
7.5
OOS
9.5
OOS
24.0
OOL
9.5
OOL
4.8
LLS
12.8
LLS
1.5
LLO
11.0
LLO

1.2
SOL
22.0
SOL
12.0
Total triglycerides containing 3 different fatty
acids.
7
Catalysts

• High temperature catalysts KOH and NaOH

3
)

• Low temperature catalysts Sodium Methoxide
  (NaOCH

8
Reaction Mechanisms
9
Catalyst Function in Interesterification
Initial removal of an ?-proton by the base
catalyst leads to the charge delocalized enolate
anion.
O
-

H2O

O
H
C
H
C
C
H
3
3
-
O
O
-
C
H
C
H
C
C
H
C
C
H
3
2
3
2
O
-
C
C
H
C
H
2
3
10
Enolate Ion Formation
O
C
O
C
H
R
2
1
-

CH3OH
O
C
O
C
H
R

O
C
H
2
2
3
O
C
O
C
H
R
2
3
-
O
O
-
O
C
C
R
O
C
C
R
1
1
H
H
O
C
O
C
H
R
O
C
O
C
H
R
2
2
2
2
O
C
O
C
H
R
O
C
O
C
H
R
2
3
2
3
-
O
C
O
C
R
1
H
O
C
O
C
H
R
2
2
O
C
O
C
H
R
2
3
11
Mechanism for Intramolecular Ester-Ester
Interchange
_
_
O
O
O
H
O
O
C
CH
R
O
C
O
C
C
C
C
H
R
1
2
2
H
R
C
R
-
1
1
O
C
O
C
H
R
O
C
C
H
R
O
2
2
2
2
O
O
C
O
C
H
R
O
C
O
C
H
R
O
C
O
C
H
R
2
3
2
3
2
3
I II
III
Enolate ion formation
Beta-Keto ester formation

Intraesterification

_
_
_
O
H
O
O
C
C
C
C
H
R
O
O
C
O
C
H
R
2
2
2
2
R
O
O
H
O
1
O
O
C
C
C
C
H
R
O
C
C
R
2
2
1
R
H
1
O
C
O
C
H
R
O
C
O
C
H
R
O
C
O
C
H
R
2
3
2
3
2
3
III
IV
V
12
Mechanism for Intermolecular Ester-Ester
Interchange
O
_
O
O
C
C
H
R
O
C
C
R
2
1
4
H

O
C
O
C
H
R
O
C
O
C
H
R
2
5
2
2
O
C
O
C
H
R
O
C
O
C
H
R
2
6
2
3
I
VI
_
O
H
O
O
C
C
C
O
R
C
H
R
VII
1
2
4
O
C
O
C
H
R
O
C
O
C
H
R
2
2
2
5
O
C
O
C
H
R
O
C
O
C
H
R
2
3
2
6
13
Mechanism for Intermolecular Ester-Ester
Interchange
Interesterification
_
Beta-Keto ester formation
R
R
1
4

O
H
O
R
R
5
_
2
R
O
C
C
C
C
H
R
R
6
R
2
4
6
3
R
IX
1
_
R
R
C
O
O
2
5
R
R
1
5
R
O
3
R
R

2
4
VIII
R
R
3
6
X
14
Random Esterification
Interesterification can be carried out to an
equilibrium condition, at which point the fatty
acids assume an almost random distribution among
triglycerides.
15
Intraesterification, Interesterification and
Equilibrium Mixture.
S
O
L
Catalyst
O
O
L
L
S
O
S
L
S
Continued reaction

S
S
S
S
S
S
O
L
S
L
S
S
S
S
S
O
O
L


L
O
L
O
L
O
S
S
S
L
O
L
O
O
O
O
L
L
O
O

L
L
L
L
O
O
L

(SUS
SSU) (SUU
USU)
UUU
SSS





16
Direct Interesterification
Interesterification can be directed away from its
usually random end-point if the fat is allowed to
crystallize during reactions. The trisaturated
glycerides crystallize first.
17
Intraesterification, Interesterification and
Equilibrium Mixture
S
O
L
Catalyst
O
O
L
L
S
O
S
L
S
Continued reaction

S
S
S
S
S
S
O
L
S
L
S
S
S
S
S
O
O
L


L
O
L
O
L
O
S
S
S
L
O
L
O
O
O
O
L
L
O
O

L
L
L
L
O
O
L

(SUS
SSU) (SUU
USU)
UUU
SSS





18
Directed Interesterification

S

O

L
1. Stearic-Stearic-Stearic 33.3 mole solid 2.
Oleic-Oleic-Oleic 8.3 mole liquid 3.
Linoleic-Linoleic-Linoleic 8.3 mole
liquid 4. Oleic-Oleic-Linoleic 24.9 mole
liquid 5. Oleic-Linoleic-Linoleic 24.9 mole
liquid
19
Effects of Different Interesterification of Lard
on Triglycerides
__________________________________________________
________________
S
()
S
U()
SU
()
U
()
3
2
2
3
__________________________________________________
________________
Natural Lard
2.0
27.0
47.0
24.0
Completely Random
4.3
23.8
44.4
27.5
Directed Random
8.4
17.4
41.4
32.9
__________________________________________________
________________
20
Intraesterification, Interesterification and
Equilibrium Mixture.
S
O
L
Catalyst
O
O
L
L
S
O
S
L
S
Continued reaction

S
S
S
S
S
S
O
L
S
L
S
S
S
S
S
O
O
L


L
O
L
O
L
O
S
S
S
L
O
L
O
O
O
O
L
L
O
O

L
L
L
L
O
O
L

(SUS
SSU) (SUU
USU)
UUU
SSS





21
Benefits of Interesterification
Lard may be given different properties by varying
the method of interesterification. One set of
conditions favors intramolecular interchange and
results in a crystal-modified lard
(CML). Conditions favoring random distribution
can be controlled to yield a partially modified
lard (PML). Conditions favoring directed
interesterification can be used to control the
GS3 content of direct interesterified lard (DIL).
22
Baking Evaluation of Modified Lards Stored at
Different Temperatures
Pound cake volume (ml)








Storage temperature (ºC )










24
30
38









Storage time (weeks)
2

16

1

9

1

4


Lard (Natural)
1475
1435
1400
1190
1400
1100


PML
1500
1445
1470
1335
1400
1295
CML
1525
1565
1535
1550
1510
1555
DIL

1505
1455
1595
1305
1440
1355
23
Applications
Shortenings The proportion of palmitic acid in
the 2-position is reduced from about 64 to 24
on random interesterification. Natural
lard beta Randomized lard beta Randomization
of lard improves its plastic range and thus makes
it a better shortening than natural lard.
24
Plasticity and Consistency
Plasticity is the changes in consistency as a
function of temperature. Consistency is the
apparent hardness at a temperature
25
Margarines High Stability Margarine Blends
1. 75 (co-randomized 40 coconut oil / 60
palm oil), 2. 10 (co-randomized 50 coconut
oil / 50 hydrogenated canola oil) and 3.
15 hydrogenated soybean oil Good
spreadability, high temperature stability, and
good eating qualities.
26
Nutritional Margarine Blends
High polyunsaturated content and low-to-zero
trans-acid containing margarines are produced by
interesterifying a blend of liquid oil and a
fully hydrogenated oil.
27
Confectionary Fats
Hydrogenated palm kernel oil is a hard butter
melting at 46?C and produces a waxy feel in the
mouth. On randomization, its melting point is
reduced to 35?C. By blending hydrogenated palm
kernel oil and its randomized product, a whole
series of hard butters with highly desirable
melting qualities (rapid melt in mouth) are
obtained
28
Confectionary Fats from Blend of Hydrogenated and
Interesterified Hydrogenated Palm Kernel Oil
SCI

Fat
M.P
.(
C)
10
20
35
38
Hydrogenated palm
46.8
74.2
67.0
15.4
11.7
kernel oil (PKO)
Int. hydrogenated
35.0
65.0
49.9
1.4
1.1
PKO
50 hydrogenated
41.7
70.0
57.4
8.7
5.
2
50 int. hydrogenated
29
Effect of Randomization on SCI of an 8020
Mixture of Lightly Hydrogenated Soybean Oil and
Palm Stearine
30
Solid Content Index of Cocoa Butter before and
after Interesterification
31
Changes in SCI of Lard by Interesterification
32
(No Transcript)
33
Cross-Sectional Structures of Triglycerides
Freedom of molecular motion
Alpha
Beta Prime
Beta
34
Double Chain Length Structures of Triglycerides
D
D
D
Alpha
Beta-Prime Beta
(Vertical tuning fork)
(Tilted tuning fork) (Stacked chair)
35
Characteristics of Triglygeride Polymorphs
__________________________________________________
______________________
Alpha
Beta-Prime Beta
__________________________________________________
______________________
Platelet
Fine needle
Long needle
m
m
m
5

1
25-50
Most loosely packed
More closely packed
Most closely packed
__________________________________________________
______________________