which its viscosity internal friction of fluids is affected by the presence of solids in suspension, as well as by temperature. Viscosity and rheology can be
affected by several factors. Smaller particle size in a constant formula will give a higher viscosity.
Tempering is the controlled cooling melted chocolate with agitation that will promote the formation of small stable fat crystals throughout the
chocolate. Besides agitation, time and temperature play an impor tant role in the tempering process. Tempering can be done manually or in an automatic
tempering unit. In general, It involves heating process of the chocolate to approximately 110 to115°F 43 –46°C to melt the fat crystals. It is then cooled
down with agitation to between 80 to 84°F 27 –29°C, and subsequently reheated to about 86 to 88°F 30 –31°C before moulding or coating. In
general, dark chocolates are tempered about 1 to 2°F 0.5 –1.0°C higher than milk chocolate 11. However, exact temperatures and procedures will depend
upon the tempering equipment and type of chocolate used. Tempering process will result in stable cocoa butter crystals which provide snap, good gloss,
proper texture, bloom resistance, contraction for demoulding, and less permeable barrier Tanabe and Hofgerber, 2006.
B. COCOA BUTTER
Cocoa butter CB is a natural fat extracted from cocoa bean which in other countries, it defines a natural fat produced from cacao nib pressing. The
total fat content of the whole bean on a dry basis is around 48 to 49 triacylglycerol is the major storage component. A mature cocoa bean can store
up to 700 mg of cocoa butter. Since a tree may produce as many as 2000 seeds a year, a single tree could yield up to 15 kg of cocoa butter annually Shukla,
2006. This natural fat will determine the final properties of chocolate product. CB is a major component of the fat phase of chocolate. It contributes 30 to 40
percent by weight to finished chocolate, and it is responsible for texture, gloss, and mouth feel of the chocolate Chaiseri and Dimick, 1989. CB is defined
by its hard and brittle texture in room temperature but has sharp melting properties below body temperature. The uniqueness of cocoa butter can be felt
when eaten, it let completely in mouth with s oft and creamy texture, also gives a cooling sensation and there is no waxy feel sensation after eating
Gunstone, 2002. CB is composed of 98-99 simple lipids and 1 -2 complex lipids.
The simple lipid fraction comprises 96.0 triacylglycerols TAGs, 2 .2 diacylglycerols DAGs, 0.2 monoacylglycerols MAGs, 0.6 free fatty
acids FFAs, and 0.9 other simple lipids D‘ Alonzo et al., 198 2. Chemical and physical properties of CB depend on its composition and distribution of
TAGs and the FFAs. Unsatura ted fatty acids in TAGs mainly consist of oleic acid 83 which in position sn -2.
The physical properties of cocoa butter is caused by the composition of TAGs,
which is 70-80, dominated by three symmetric triacylglycerols, saturated-unsaturated-saturated StUSt, which are palmitic -oleic-stearic
POS, 36-42, stearic- oleic-stearic SOS, 23- 29, palmitic-oleic-palmitic POP, 13-19 and with trace amounts of asymmetrical tri acylglycerols
PPO, PSO, and SSO Wainwright, 1996. The unique triacylglycerols composition together with the extremely low level of di acylglycerols gives
cocoa butter its desirable physical properties and ability to recrystallize during processing in a stable crystal modifica tion. The complexity of the
crystallization of cocoa butter is because triacylglycerols can crystallize in a number of different crystal modifications, depend s on triacylglycerols
composition and on crystallizing and tempering conditions during manufacturing and storage Shukla, 1995. In addition, the triacylglycerol
composition is affected by the origin of the cocoa beans. The fatty acid composition, various analytical constants, and triacylglycerol composition of
different cocoa butters are given in Table 1. It is generally accepted that cocoa butter can exist in six
polymorphic forms, although many believe forms V and VI to be identical. Forms I to IV are termed as unstable as they have a tendency to convert to the
higher forms, V and then VI. Although form V will eventually convert to the higher form, form VI, it is termed stable, as this conversion occurs over a long
time 12–18 months at 20 ºC. During the manufacture of chocolate, a
tempering stage is necessary to ensure that all the CB crystallises in form V, thereby making the product stable and giving it a high level of gloss and snap.
Table 1
. Characteristic and Composition of Cocoa Butter from Different Countries.
Factor Ghana
Ivory Cost Brazil
Malaysia
Iodine value Melting point
C Diacylglycerol
Free fatty acids Fatty acid composition :
Palmitic Stearic
Oleic Linoleic
Arachidic TAG composition :
Trisaturated Monounsaturated
POP POS
SOS Diunsaturated
Polyunsaturated Solid Fat Content pulsed
NMR- tempering at 26 C for
40 hours 20
C 25
C 30
C 35
C 35.8
32.2 1.9
1.53 24.8
37.1 33.1
2.6 1.1
0.7 84.0
15.3 40.1
27.5 14.0
1.3
76.0 69.6
45.0 1.1
36.3 32.0
2.1 2.28
25.4 35.0
34.1 3.3
1.0 0.6
82.6 15.2
39.0 27.1
15.5 1.3
75.1 66.7
42.8 0.0
40.7 32.0
2.0 1.24
23.7 32.9
37.4 4.0
1.0 Trace
71.9 13.6
33.7 23.8
24.1 4.0
62.6 53.3
23.3 1.0
34.2 34.3
1.8 1.21
24.8 37.1
33.2 2.6
1.1 1.3
87.5 15.1
40.4 31.0
10.9 0.3
82.6 77.1
57.7 2.6
Source: Sukhla 1995
The percentage of solid fat in a typical CB at different temperatures is shown in Table 2. The level of liquid fat present in a product is significant , not
only in determining the sensory particularly textural quality but also in influencing the shelf-life of chocolate products. The fast-melting characteristic
of CB between 30 ºC and 35ºC is responsible for fast meltdown of chocolate in the mouth. A high solid fat content at body temperature would be perceived
as an unpleasant waxy mouthfeel Subramaniam, 2000.
Table 2
. Solid Fat Content SFC of Cocoa Butter Temperature
C Solid Fat
20 75.5
25 70.5
30 41.0
32.5 15.0
35 0.6
Source : Soon 1991
Figure 1. Cocoa butter SFC Curve Depending on Temperature
Cocoa butter SFC values calculated at temperatures below 25 C
characterize its hardness, while the values calculated at temperatures between 25 and 30
C indicate the resistance of cocoa butter to heating. In the range of 27 to 33
C, intensive melting of cocoa butter occurs, bring s about the cooling sensation in the mouth and flavour release Torbica, et. al., 200 6.
C. COCOA BUTTER ALTERNATIVES
