Keywords
Theobroma cacao
-
Malvaceae
- cocoa butter - pharmaceutical excipients - drug delivery system
Introduction
The discovery of cocoa beans has made them popular for decades. Cocoa butter is the
fatty seed found inside a cocoa pod, a fruit of the Theobroma cacao plant. T. cacao is a kind of small tree that grows naturally in the lowest areas of the Amazon basinʼs
evergreen rainforest [1]. Cocoa butter has the scientific name Theobroma cacao L., as well as other scientific names such as Theobroma pentagonum Bernoulli and Theobroma sativum (Aubl.) Lign & Le Bey. It belongs to the domain Eukaryota under the kingdom of Plantae.
More specifically, T. cacao L. is part of the subkingdom Tracheobionta, superdivision Spermatophyta, division
Magnoliophyta, and further classified under the phylum Spermatophyta. It is categorized
in the order Malvales and is a member of the family Malvaceae in the genus of Theobroma
[2]. Therefore, the complete botanical designation for the source of cocoa
butter is Theobroma cacao L., from the family Malvaceae. The origin of this tree is from tropical rainforest
areas of Central and South America. The raw materials used to produce chocolate, cocoa,
and cocoa butter are from the seeds of T. cacao plant. Following harvesting, the cocoa fruit is cracked to obtain the seed, then
the pulp and seeds are separated by fermentation. The pulp is used in distilleries
and the seeds are used to prepare cocoa powder, chocolate, and cocoa butter [3]. The naturally stable fat known as cocoa butter is sourced from the cocoa bean of
T. cacao. It solidifies at room temperature but melts to liquid at human body temperature.
Thus, it has been widely used in different industries for many years. It has been
commonly used as a food flavoring, a cosmetics additive, and in food biotechnology
[4], [5], [6].
Natural products serve as a fundamental foundation for the manufacturing of materials
needed in different industries including the food, pharmaceutical, and cosmetic industries.
However, there are some disadvantages when utilizing natural products as the source
of raw materials. For example, instability and uncertainty in the yield and production
of natural products. Thus, a change in strategic approaches to material production
is required due to the growing population-related resource demand, growing areas becoming
less viable due to environmental degradation, and extinction of plants because of
climate change [7]. A review paper by Applequist et al. discussed the impact of climate change on medicinal
plants. Medicinal plants contribute a lot to human health. They constitute the main
component for citizens of most developing countries and the number of its consumers
are increasing in wealthier countries [8], [9], [10]. To assure economic efficiency and the widespread use of limited raw materials with
high added value, a variety of advanced innovative technologies have been developed
to substitute natural products in order to address the issue at hand [11], [12]. T. cacao plants are used to produce cocoa butter, which is a value-added product employed
in the processing of cocoa beans. High levels of saturated fatty acids and low levels
of highly unsaturated fatty acids make up the majority of ingredients in cocoa butter,
while the composition is totally dependent on plant variety and the culture circumstances.
In other words, cocoa butter originating from different countries contains different
compositions of saturated and unsaturated fatty acids [13]. The condition of increasing demand and supply shortages leads to an increasing
interest
in cocoa butter alternatives. Numerous approaches have been tried to combine various
fats from exotic plants with palm oil to formulate compounds with a similar lipid
composition to cocoa butter [5]. Nowadays, cocoa butter has been utilized extensively in industries other than the
food industry, such as the pharmaceutical industry and cosmetics industry. Thus, this
review aims to comprehensively discuss and explore the different aspects of cocoa
butter, focusing on its characteristics, uniqueness, applications, and emerging uses
in various industries.
Research Methodology
The key word “cocoa butter” was searched in Google Scholar and related articles were
referred to and reviewed.
Production of Cocoa Butter
Production of Cocoa Butter
The production of cocoa butter starts with the removal of pulp and cocoa beans, and
discarding rind. The pods are opened to reveal the beans. Then, the pods with detached
rinds are placed in trays or heaps to undergo sweating and fermenting. At this step,
natural liquefying enzymes present in the pulp are applied to dissolve the pulp. This
process is referred to as liquefaction of the pulp, which helps to separate the bean
from the pulp in an easy way. For the purposes of storage and transportation, conventional
or unconventional heat sources are utilized to remove excess moisture from the separated
beans. After being cleansed to get rid of unwanted materials, the dried beans are
roasted under carefully monitored conditions. This procedure produces a proper chocolate
flavor. The roasted beans are cracked to remove the shell. After being cracked, the
beans go through a winnowing process, in which a gentle airflow is used to deshell
them. The deshelled and cleaned nibs obtained
are ground to produce the liquor or cocoa mass. Cocoa liquor can be directly used
or blended with other ingredients for chocolate making [3].
Cocoa liquor is the primary source that is used to extract cocoa butter in the absence
of other resources. Several approaches have been used to extract cocoa butter from
the cocoa mass. For example, mechanical press, supercritical fluid extraction (SFE),
hydraulic press, and solvent extraction are some of the examples of methods used [3]. According to Asep et al., SFE is a technique using carbon dioxide as a solvent
and offers an excellent option for chemical solvents when it comes to the removal
of cocoa butter from various plant matrices. SFE offers multiple essentials over current
conventional techniques, most notably the capacity to generate products that are completely
free of processing residues. SFE is also an alternative option that is time-saving
and friendly to the environment [14]. Thus, SFE would be the best method for food grade application from the methods
mentioned above [3].
Composition of Cocoa Butter
Composition of Cocoa Butter
A blend of unsaturated and saturated fatty acids makes up cocoa butter. A high proportion
of highly saturated fatty acids and a low proportion of highly unsaturated fatty acids
can be found as the main components of cocoa butter [5]. Jahurul et al. suggested that there are three major triglycerides that contribute
92 – 96% of the total lipid content of cocoa butter, including glycerol-1,3-dipalmitate-2-oleate
(POP), glycerol-1-palmitate-2-oleate-3stearate (POS), and glycerol-1,3-distearate-2-oleate
(SOS). Out of these three triglycerides, POS occupies the greatest proportion, with
a range of 42.5 – 46.4% yield, followed by SOS (27.8 – 33.0%) and POP (18.9 – 22.6%).
Besides triglycerides, there are other components such as fatty acids present in cocoa
butter, which include palmitic acid (C16) 25 – 33.7%, stearic acid (C18 : 0) 33.7 – 40.2%, oleic acid (C18 : 1) 26.3 – 35%, and linoleic acid (C18 : 2)
1.7 – 3%. The various types of fatty acids found in cocoa butter contribute about
98% of total fatty acids [13]. In a study conducted by Erickson et al., several types of vitamin E, including
α-tocopherol, β-tocopherol, and γ-tocopherol, were found in cocoa butter. The amount of β-tocopherol is higher, which is followed by α-tocopherol and γ-tocopherol [15].
Properties of Cocoa Butter
Properties of Cocoa Butter
The composition of triglycerides present in cocoa butter determines its properties.
Cocoa butter starts to melt at a temperate range of 27 to 35 °C. Cocoa butter remains
in a solid state at room temperature, and it is hard and brittle, whereas its hardness
depends on the solid fat content. The hardness of cocoa butter is also affected by
the nature of crystalline lattice [3].
Different countries of origin result in variation between cocoa butter in terms of
composition. Asian cocoa butters tend to have higher levels of stearic acid and a
lower palmitic acid content than African cocoa butters, resulting in higher SOS/POP
ratios. Comparing cocoa butter from other regions, South American cocoa butters typically
contain higher unsaturated fatty acid levels, which lead to higher stearic-oleic-oleic
triglycerides (SOO) (palmitic acid, stearic acid, arachidic acid, and oleic acid)
levels and softer cocoa butter. The melting characteristics of cocoa butters are altered
by the variations in triglyceride makeup. In general, SOS melts at a higher temperature
than POS, which, in turn, melts at a higher temperature than POP. In summary, Asian
cocoa butters contain higher SOS, and POS has a higher solid fat content when compared
to West African or South American cocoa butters. Triglycerides with larger percentages
of unsaturated fatty acids melt at a lower
temperature. Generally, cocoa butters produced from South American have smaller percentages
of lower solid fat content than that of Asian or West African cocoa butters [16].
Polymorphism of Cocoa Butter
Polymorphism of Cocoa Butter
Polymorphism is defined as the ability of a substance to display different structures.
Cocoa butter has at least six distinct structures or crystal forms. Variations in
the structures or crystal forms result in different molecular arrangements and thus
influence the properties of cocoa butter in different states. Cocoa butter exhibits
six totally different crystal polymorphic forms with varying melting temperatures
and complex crystallization behavior [17]. The Wille and Lutton nomenclature is the most frequently used nomenclature for
cocoa butter polymorphism. [Table 1] shows the melting point of each form from the Wille and Lutton nomenclature, which
was adapted from Quing et al. [4]. According to this nomenclature, form IV is the most stable form, with a melting
point of 36 °C, whereas form I is the least stable form, melting at 16 – 18 °C. On
the other hand, form V cocoa butter is the
more desirable variety since it is also stable and more visually appealing, with a
shiny smooth texture. Along with that, form V cocoa butter has a lower melting point,
which enables it to melt more quickly in the mouth, than form VI cocoa butter. Tempering
is a commonly used method to pre-crystallize form V cocoa butter. However, it will
gradually evolve into form VI, with a higher melting point and stability over time.
Form IV cannot be made on its own but slowly develops from form V [4], [18], [19].
Table 1 Melting points of cocoa butter for each form from the Wille and Lutton nomenclature
[4].
|
Polymorphism form
|
Melting point (°C)
|
|
I
|
17.3
|
|
II
|
13.3
|
|
III
|
25.5
|
|
IV
|
27.3
|
|
V
|
33.8
|
|
VI
|
36.3
|
Applications of Cocoa Butter in Various Industries
Applications of Cocoa Butter in Various Industries
Food industry
Cocoa butter is the main ingredient in the manufacturing of confectionery products
such as chocolate making. It is a pale yellow liquid with a unique aroma and chocolate
taste. It is significant and the only continuous fat phase that aids in the dispersion
of other ingredients in chocolate [3], [20]. The role of cocoa butter in chocolate making includes providing texture, flavor,
and mouthfeel. Cocoa butter has a melting point 27 to 35 °C. The composition in cocoa
butter consists of palmitic, stearate, and oleic fatty acids, giving it a smooth melting
texture when consumed. In a previous study, the researchers compared cocoa butter
and cocoa butter alternatives in chocolate making. The study indicated that cocoa
butter substitutes (CBSs) are more acceptable than cocoa butter replacers (CBRs) and
cocoa butter equivalents (CBEs) in chocolate making among cocoa butter alternative
(CBA) subgroups. The reasons that the use
of CBRs and CBEs are not as preferable as CBSs in chocolate making has been studied
and is stated in [Table 2]
[21], [22].
Table 2 Limitation in the use of cocoa butter replacers (CBRs) and cocoa butter equivalents
(CBEs) in the production of chocolate [21], [22].
|
Factors
|
CBRs
|
CBEs
|
|
Melting point (cocoa butter: 35 °C)
|
Average melting point: > 38 °C. The chocolate barʼs character becomes firm at this
state, thus rendering it difficult to melt in the mouth.
|
Average melting point: 18.5 ± 21.78 °C. Its stability varies due to its wide temperature
range.
|
|
Mixing
|
It can only be combined with cocoa butter in extremely small quantities.
|
It cannot be mixed in any ratio.
|
|
Impurity compound
|
Elaidic acid (E)
|
Diglycerides, diacyl-glycerol (DAG)
|
|
The availability of raw materials
|
Groundnut oil and hydrogenated oil can be found in great abundance. However, they
have not been developed to be as efficient as possible.
|
Shea butter, kokum butter, illipe butter, and sal fat. They are quite rare.
|
|
Taste
|
Cocoa butter has a variable taste in which other tastes occasionally come up. This
condition might be affected by the fatty acidsʼ origin.
|
|
Flavor
|
Chocolate-based products usually have an erratic taste. In addition, other flavors
still appear.
|
Other than confectionery products, cocoa butter is also widely used for baking. The
addition of cocoa butter in cakes, biscuits, pastries, and cookies aims to add richness
and moisture to the products. A study done by Quek et al. titled “Effects of Cocoa
Butter and Cocoa Butter Equivalent in a Chocolate Confectionery on Human Blood Triglycerides,
Glucose and Insulin” aimed to evaluate and conduct research on the effects of sal
fat and cocoa butter, which have comparable chemical structures, on lipidemia, insulinemia,
and postprandial glycemia. Nineteen male participants in good health fulfilled the
inclusion criteria and were included in the study. The researchers concluded that
when compared to a brownie made with cocoa butter and SAL seed oil (SL), the brownie
made with cocoa butter oleogel (CBOG) and SAL seed oleogel (SLOG) had a significantly
smaller increase in plasma insulin and triglycerides. The studyʼs findings also demonstrated
that there is no difference in
metabolic effects between cocoa butter and SL, and between CBOG and SLOG. This circumstance
points out that Sal fat may be a suitable replacement for cocoa fat in the production
of chocolate confectioneries. Additionally, the results demonstrated that their metabolic
reaction is the same. Thus, there is no threat to the publicʼs health when SAL seed
and cocoa butter are “interchanged” [23].
Cosmetic industry
The functions of cocoa butter are not only limited to the food industry. It is also
widely used in the cosmetics industry due to its nourishing and thickening properties.
The application of cocoa butter in skincare products proved that cocoa butter provides
numerous benefits to the skin, including moisturizing, aiding in skin hydration, anti-inflammatory
effects, and others. According to Naik and Kumar, cocoa butter made from starch and
palmitic acid contains a high proportion of saturated fat and trace amounts of theobromine
and caffeine. Additionally, it has fat-soluble antioxidants such as vitamin E in the
forms of β-, α-, and γ- tocopherol. Cocoa butter is commonly used in the formulations of skincare products
such as lotions, moisturizers, lip balms, hand creams, sunscreens, and others because
of its antioxidant and hydrating features, which exert an antiaging effect [3].
Our skin works through various mechanisms to keep skin healthy and intact. Gyedu-Akoto
et al. mentioned that the maintenance of skin health is significantly affected by
natural moisturizing factors (NMFs) or substances that replicate the structure and
function of healthy skin. While oil and fat components produced by the skin act as
lubricants to moisturize the skinʼs surface and prevent evaporation, the condition
of skin will be affected when lipid and NMF content is reduced. Surface roughness,
flaking, fine wrinkles, and an unpleasant tight feeling may appear on the affected
skin [24], [25], [26]. Gasser et al. compared the effects of cocoa polyphenols and cocoa butter on the
skin. The study concluded that the application of cocoa polyphenols for at least 5
days can improve the structure of skin. On the other hand, it takes cocoa butter at
least 12 days to exhibit the same activity. When
coupled with cocoa butter, the most ex vivo metrics related to skin elasticity and tone are enhanced at a dose of 0.5 to 0.75%
by cocoa polyphenols. Improvement in the overall morphology of the skin as well as
the expression of type I and type IV collagen and glycosaminoglycans (GAGs) on the
skin were observed when cocoa butter was paired with cocoa polyphenols to be applied
on the skin [27].
Monounsaturated free fatty acids (FFAs) such as oleic acid are present abundantly
in cocoa butter. Monounsaturated FFAs may disrupt the skin barrier and thus act as
permeability enhancers [28]. Cocoa butter is one type of fat that can prevent evaporation on the skin and provides
lubrication for the skin surface. Thus, the lipid content of the skin can be maintained
and result in a good texture of the skin [24], [29]. Many cosmetic products use cocoa butter as a raw material. However, one study found
that it is rare to find products that use cocoa butter as a raw material for solid
perfume. A study done by Septiyanti et al. investigated solid perfume made by mixing
a wax base, carrier oil, and essential oil as fragrances followed a heating process.
Several concentrations of cocoa butter for solid perfume were tested and optimized
in this study. The outcomes revealed that the features of the
finished products were remarkably impacted by the concentration of cocoa butter. Due
to the absence of any new chemical groups in the finished products, the researchers
involved stated that the production procedure merely involved physical processes that
do not have an impact on the stability of the products. According to the results of
an organoleptic test, the product with a 30% cocoa butter concentration was chosen
as the optimum formulation [29].
Pharmaceutical industry
The characteristics and polymorphisms of cocoa butter have attracted the attention
of researchers in the field of the pharmaceutical industry. Cocoa butter has been
utilized in the development of a drug delivery system. A review published by Ramos-de-la-Peña
et al. [30] suggested that cocoa butter had been studied at the nanoscale, and this is a major
advance in the development of nano-delivery systems. Besides pharmaceutical products,
these nanostructures can encapsulate different compounds used in the food industry,
too, including food-drug ingredients, antimicrobials, vitamin, antioxidants, flavorings,
and drugs. A readily available core and a protective physicochemical wall or shell
constitute a nanocarrier. They have been aimed for applications of targeted delivery
as well as controlled delivery of bioactive ingredients and drugs. Lipid-based systems
and biopolymers (protein and polysaccharides) are the two categories of a nano-delivery
system. The characteristics of carbohydrate and protein networks make them impossible
to precisely control thermal and chemical process during manufacturing processes.
Thus, this condition limits their use at industrial scales. Lipids have demonstrated
that they are more efficient in encapsulating for large-scale productions [30]. Polymorphic transition in solid lipid nanoparticles (SLNs) depended on multiple
factors and variables in the study. For instance, the uses of lipid(s) and emulsifiers
generated particle size and the applied temperature during cooling and storage might
exert an effect on the polymorphic transition in SLNs [31], [32]. As per Ramos-de-la-Peña et al. [30], the solid lipid portion of SLNs is often where cocoa butter resides. Examples include
when the bioactive ingredient and the heated emulsifier solution are mixed with melted
cocoa butter
and other fats [30], [32].
Furthermore, nano-drug delivery systems have become another important drug delivery
method in cancer therapy. According to Chavda et al., the role of lipid in lipid-based
nanoparticles act as penetration enhancers of the drug, thus enhancing drug solubility
and diffusion from the lymphatic to the circulatory system. Food-grade lipids such
as cocoa butter and olive oil have been used to synthesize cardamom essential oil
(CEO)-loaded nanostructured lipid carriers (NLCs). This modification results in a
small size, improved loading capacity, and provides good physical and chemical stability
[33], [34]. Moreover, a review article titled “Applications of Novel Drug Delivery Systems
for Enhancement Bioavailability of Antiretrovirals with Special Focus on Nanotechnology”
discussed the employment of nanotechnology in antiretroviral therapy. Several drugs
such as saquinavir, stavudine, and delavirdine were prepared using cocoa
butter and tripalmitin as a polymer-based nanocarrier system to increase the permeability
of drugs across the blood-brain barrier [35].
Another article published by Quing et al. stated the use of cocoa butter as a novel
excipient for oral tablets. Research has been done on the development of fast melt
tablets (FMTs) without any active components by employing the freeze-casting technique,
with sucralose and cocoa powder as excipients [4], [36]. Moreover, cocoa butter is a fat that can act as a lubricant in tablet formulations.
A study done by Adeagbo and Alebiowu compared the lubricating properties of cocoa
butter. The cocoa butter that was co-processed with magnesium stearate and talc (CMT)
had an impact on the mechanical properties of the tablets, as reflected by their tensile
strength (T) and brittle fracture index (BFI). Tablets containing CMT had lower T
and BFI values than tablets containing talc and magnesium stearate (MT). The findings
indicated that although CMT lowered the granulesʼ plasticity, it improved their flow
rate and contributed to
formulating tablets with a lower risk to cap or laminate. This study concluded that
cocoa butter is easily accessible and a reasonably priced lipid that can be co-processed
with a magnesium stearate/talc mixture to effectively lubricate granules. It may also
be useful in reducing the risk of lamination and capping in formulations [37]. According to Quing et al., there were researchers that studied and developed a
palatable medicated chocolate to deliver salbutamol and ambroxol for pediatric care.
The chocolate-based formulation exhibited stability, good therapeutic efficacy, and
a huge preference [4].
As time progresses, technologies undergo exceptional levels of advancement. Three-dimensional
(3D) printing has been developed and now its applications can be found in our daily
life. Using digital designs as a starting point, 3D printing is an additive manufacturing
technique that creates an actual substance layer-by-layer. This technique had been
used to print chocolate. Chocolate possesses the characteristics of melting at a predetermined
temperature and solidifies quickly when it sticks to the layer before it. This is
a crucial characteristic to be focused on when selecting materials used for 3D printing
[38]. Hence, cocoa butter is often utilized as the “ink” for production of the 3D printing
of chocolate. After printing, the chocolate obtained does not need any other process,
which makes for an easier and shorter manufacturing process [39].
Alternatives of Cocoa Butter
Alternatives of Cocoa Butter
The cultivation of the T. cacao plant, the main source of cocoa butter, is limited to tropical areas due to its requirement
of growing conditions such as climate and temperature. Other factors including natural
disasters and infectious plant diseases may also affect the yield of cocoa beans.
As time passed, the demand of cocoa butter increased due to rapid global economic
growth. Eventually, a deficiency of cocoa butter happened, which resulted in a price
increase for cocoa butter. Thus, CBAs have been explored in order to cover the increased
demand for cocoa butter. There are various types of alternatives for cocoa butter
that have been classified into different categories based on their fat composition.
CBAs are classified into three types: CBSs, CBEs, and CBRs. According to Patel et
al., non-lauric plant fats, known as CBEs, are comparable to cocoa butter in both
physical and chemical aspects. CBEs can be mixed with cocoa butter in any quantity
without affecting its
characteristics. Conversely, CBRs are non-lauric fats having similar fatty acid distribution
as that of cocoa butter. Unlike CBEs, CBRs are only slightly compatible with cocoa
butter because their triglyceride structure is completely different. Lastly, CBSs
are lauric plant fats that are chemically totally different than cocoa butter, although
they resemble the physical similarities of cocoa butter. CBSs are only suitable to
be used as a complete substitution for cocoa butter. [5]. In another words, CBRs can be used to replace cocoa butter. [Fig. 1], adapted from Budianto and Kusmardini, shows the classifications of CBAs [21].
Fig. 1 Classification of cocoa butter alternatives.
CBSs are another replacer of cocoa butter in the food industry. A limited quantity
of CBSs can be implanted with cocoa butter without influencing the processing, and
physiological and melting characteristics. CBSs do not necessarily have the same or
similar physicochemical properties as cocoa butter. The degree of compatibility basically
depends on the quality. CBSs contain high amounts of lauric and myristic acids. However,
CBSs are chemically different from cocoa butter. So, CBSs are used as a whole replacement
for cocoa butter [3]. Despite exhibiting an eutectic effect and chemical differences, CBSs do not require
tempering, which is a step that is typically required in the final product of other
CBAs [40], [41], [42]. Thus, CBSs can be used for products that require good stability since they do not
require a tempering process like cocoa butter.
Due to similar physical and chemical characteristics, CBEs can be mixed with cocoa
butter in any ratio without changing the end productsʼ processing or melting and rheological
characteristics. The end products will have similar characteristics as products utilizing
cocoa butter as a raw material. Like cocoa butter, the main fatty acids found in CBEs
include oleic acid, palmitic acid, and stearic acid. Most CBEs are made by combining
various mixtures of palm oil, palm oil fractions, shea and illipe, sal and mango kernel
fats, and other ingredients. Typically, CBEs are less expensive than cocoa butter.
CBEs are further distinguished into two subgroups: cocoa butter extenders (CBEXs)
and cocoa butter improvers (CBIs) [3], [22]. CBIs are similar to CBEs; however, CBEXs cannot be used in combination with cocoa
butter in any amount. This is because CBIs have a high concentration of solid triglycerides.
Thus, they are
frequently employed to improve soft cocoa butter [3]. The hardness and melting resistance of chocolate are attributed to the types of
CBAs used in the manufacturing process. Chocolate made from CBIs, which are SOS-rich
fats, or CBEs that are highly solid at 36 °C, are sturdy and melt-resistant. According
to Reddy and Prabhakar, chocolate and confectionery products produced from cocoa butter
are inadequate for use in hot climates due to the high risk of melting. Therefore,
lipids resistant to high temperatures must be used in these types of climates [42]. It has been suggested that adding SOS triacylglycerols or SOS-rich fats to cocoa
butter or chocolate can improve the quality of chocolate, prevent fat bloom, make
the butter harder, and shorten the tempering time. When cocoa butter fully melts,
CBIs typically have higher temperature profiles than cocoa butter and continue to
be solid [43].
Lastly, CBRs are another option provided to replace cocoa butter. Cisse and Yemiscioglu
stated that CBRs do not contain lauric acid, so-called non-lauric fat [44], [45]. CBRs are synthesized from fractionated vegetable fats and have a high tolerance
for cocoa butter. They are utilized to give final products glass retention and a sharp
meltdown without tempering. CBRs are mostly used in compound coatings because of their
specific compatibility with cocoa butter. It can be mixed with cocoa butter to produce
compounds that work well for both moldings and coatings. Since the fats in CBRs are
not from the lauric region, the resulting products will not taste soapy. The fact
that compounds produced using CBR do not require tempering is crucial [46], [47]. As a consequence of the differences of their chemical properties, CBRs and cocoa
butter can be combined in very
small amounts without affecting the final product [44].
There are several additional benefits provided by CBAs. Lauric and hydrogenated fats
are usually used to substitute cocoa butter. Blends of palm oil mid-fraction and stearic
acid-rich tropical butter, known as CBEs, have high oleic and stearic acid contents
without changing plasma blood cholesterol levels. Consequently, CBEs offer a viable
and healthier substitute for cocoa butter. [Table 3] was adapted from Naik and Kumar and gives a summary in terms of the different properties
of CBAs [3].
Table 3 Properties of subgroups of cocoa butter alternatives [3].
|
Properties
|
CBE
|
CBR
|
CBS
|
|
POP: 1,3 dipalmitin-2-monooleato glycerol, POS: 1-palmito, 2-olein, 3-sterin glycerol,
SOS: 1,3 distearinmonooleate glycerol, PEE: Triglycerides with one palmitic acid (P)
molecule and two erucic acid (E) molecules, SEE: Tryglycerides with one stearic acid
(S) molecule and two erucic acid (E) molecules, LLL: Triglycerides with three linoleic
acid (L) molecules, LLM: Triglycerides with two linoleic acid (L) molecules and one
myristic acid (M) molecule, LMM: Triglycerides with one linoleic acid (L) molecule
and two myristic acid (M) molecules
|
|
Types of fatty acids
|
Plant fats without lauric acid
|
Non-lauric acid fats
|
Fats containing lauric acid
|
|
Physical and chemical properties
|
Similar to cocoa butter in terms of its physical and chemical characteristics, such
as melting point and polymorphisms
|
Similar to cocoa butter in terms of distribution, but its structure is triglycerides,
which is completely different
|
Chemically different to cocoa butter, only similar to cocoa butter in terms of some
physical similarities
|
|
Mixing properties
|
Able to be mixed with cocoa butter in any quantity without changing the characteristics
of cocoa butter
|
Only able to be mixed with cocoa butter in small quantity
|
Only suitable to fully (100%) substitute cocoa butter
|
|
Main fatty acid
|
Palmitic (P), stearic (S) oleic acid (O), Linoleic (L), arachidic acid (A)
|
Elaidic acid (E), stearic acid (S), palmitic (P), linoleic (L)
|
Lauric acid (L), myristic acid (M)
|
|
Main triglycerides
|
POP, POS, SOS
|
PEE, SEE
|
LLL, LLM, LMM
|
|
Examples
|
Sal fat, kokum butter, shea butter, palm oil, illipe butter
|
Oil rape seed oil, cotton seed oil, palm olein, hydrogenated oil, soya oil, ground
nut oil
|
Palm kernel oil, MCT, cocoa oil
|
Applications of Cocoa Butter Substitutes in Various Delivery Systems
Applications of Cocoa Butter Substitutes in Various Delivery Systems
Chocolate-based drug delivery system
Research done by Biswas et al. studied and compared the physical, rheological, and
sensorial properties and bloom formation of dark chocolate made with cocoa butter,
CBSs and blends of both cocoa butter and CBSs. Characterization of chocolate made
has been done, which includes bloom formation, rheological, textural behaviors, polymorphism,
melting profiles, and particle size distribution (PSD). The overall characterization
outcomes suggested that the physical and sensory features of chocolate with 5 g CBS/100 g
blend were similar to those of cocoa butter chocolate. However, compared to cocoa
butter chocolate, chocolate with 20 g CBS/100 g blend demonstrated noticeably inferior
sensory qualities, especially flavor acceptance and hardness [48].
In addition, a study done by Karavasili et al. moved a big step toward research about
the application of cocoa butter in oral dosage forms. This study worked on the incorporation
of both hydrophilic and lipophilic drugs in chocolate-based dosage forms using cocoa
butter as the raw material employing extrusion-based 3D printing. This study investigated
the use of corn syrup and bitter chocolate for the preparation of the ink formulations
to develop a pediatric-friendly oral dosage form [49].
Lipid-based drug delivery system
Cocoa butter has been used in the preparation for pharmaceutical and probiotics delivery
applications. Research done by Satapathy et al. employed whey protein isolate (WPI)
solution as the aqueous phase while cocoa butter was used as the fat phase in the
formulation of emulgels. In this study, cocoa butter served as emulgelʼs structural
agent. Milky white emulsions were formed when the WPI solution was added to the pale
yellow-colored molten fat (cocoa butter). Previous research revealed that the amount
of unsaturated fatty acids in fats may influence how the fats crystallize [50], [51]. In this case, fat crystals are not surface active. Hence, emulsifiers have been
utilized to stabilize the fat-aqueous interface of the biphasic formulations. Moreover,
the aqueous component of oil-in-water emulsions becomes more viscous when hydrocolloids
are added, thus stabilizing the emulsion [51], [52]. WPI was suggested to be amphipathic naturally, which gives it surface active properties
[51], [53]. Therefore, it is incorporated within the aqueous phase in this study. As an alternative
to chocolate, the blend of cocoa butter and WPI-based emulgels can be considered for
the delivery of probiotics and antimicrobial medications with longer shelf lives [51].
On the other hand, cocoa butter serves as a solid lipid in nano-delivery systems.
Nano-delivery systems are classified into biopolymer, which consists of proteins and
polysaccharides, and lipid-based systems. However, thermal and chemical processes
cannot be controlled accurately in carbohydrates and protein networks [54], [55]. Instead, lipids were shown to be more encapsulation efficient and suitable for
large-scale production [55], [56]. Ideally, a delivery system should be able to incorporate the encapsulated compounds
into food matrices with good physicochemical stability and maintain organoleptic qualities
while using natural ingredients and solvent-free production techniques. It should
maximize the uptake of encapsulated substances upon consumption and guarantee regulated
release in reaction to a particular environmental stimulus. Lastly, it should be
able to easily scale-up for industrial production [55], [57].
Formulation of oral dosage forms
The oral route of administration is always the most popular and preferred way for
patients to take their medications. The usage of cocoa butter has been involved in
the formulation of tablets recently. Cocoa butter has been used to produce FMTs in
research done by Liew et al. due to its unique characteristics and properties. Cocoa
butter FMTs provide several benefits compared to conventional tablets in terms of
the manufacturing process. Expensive and huge machines such as tableting machines
are not required for the production of cocoa butter FMTs. This manufacturing approach
provides a lower capital expenditure commitment. This is because, unlike traditional
orally disintegrating tablets (ODT) manufacturing techniques, cocoa butter FMT production
just needs a freezer and a mold, both of which are readily available and reasonably
priced for the majority of small- and medium-sized manufacturing facilities. In this
study, the formulation with cocoa butter and 15% corn starch
showed acceptable results for characterization tests. The dissolution profile, one
of the most important parameters, was comparable to the innovator product [58].
Moreover, cocoa butter was used as a taste masking agent for ibuprofen, which has
a bitter taste. According to an article published by Obaidat et al., supercritical
fluid technology was used to formulate tasteless cocoa butter microparticles containing
ibuprofen. The drugʼs remarkable dispersibility within the polymer was revealed by
physicochemical characterizations of the microparticle synthesized. The absence of
a significant drug-polymer interaction was confirmed by DSC (Differential Scanning
Calorimetry) and FTIR (Fourier Transform Infrared Spectroscopy) studies, with a few
minor variations that might be attributed to physical interactions. The synthesized
microparticles contain a good percentage of drug content, and the particle size analysis
indicated that they could be easily formulated into various dosage forms. Medication
release was enhanced after 30 min, which is appropriate for flavor masking formulas.
Consequently, this developed approach was promising in
masking ibuprofenʼs taste, which can further be formulated to a suitable pediatric
dosage form [59].
Formulation of suppositories
Besides the oral dosage form, cocoa butter has also been studied for the preparation
and formulation of suppositories. The development of suppositories dosage forms is
not that advanced and fast-paced compared to the development of oral dosage forms.
This might be due to the convenience provided by oral dosage forms, resulting in the
slow-paced development of suppositories. According to Melnyk et al., the global suppository
market is currently limited due to certain inconveniences for the patients, although
suppositories have a very long history. This condition results in the insufficiency
of the development of new drugs in this dosage form. However, suppository is the preferred
option compared to oral dosage forms under certain conditions. For example, itʼs not
suitable to give medications in tablet or suspension form to infants. It is generally
acknowledged that the therapeutic effect of suppositories is due to the interaction
of the medicinal substance and the base. To
determine the stability of a connected-dispersed system, one of the most crucial factors
is the baseʼs ability to supply the required structural and mechanical qualities.
The European Pharmacopoeia and the State Pharmacopoeia of Ukraine categorized the
suppository bases used in the manufacturing of this dosage form as hydrophobic, hydrophilic,
and diphilic [60]. While there are six main classes of suppository bases according to the USP, namely,
cocoa butter, CBSs, glycerin gelatin, polyethylene glycol, surfactant basis and tablet
suppositories or inserts [61].
In general, cocoa butter is made up of a mixture of triglycerides of saturated and
unsaturated fatty acids. Thus, cocoa butter is hydrophobic and does not absorb a significant
amount of water since it does not contain an emulsifier. Cocoa butter is a good alternative
to produce a soft base when the necessary equipment is absent. This is because the
base produced from cocoa butter is soft, does not irritate sensitive membrane tissue,
and is easily accessible and convenient [60]. However, there is no ideal and perfect excipient. Cocoa butter has a few disadvantages
that limit its uses as a suppository base. Cocoa butter is sensitive to temperature
and has a relatively low melting point. Thus, cocoa butter and its suppositories must
be stored either at a controlled room temperature or in the refrigerator. The temperature
for storage should not exceed 25 °C to prevent melting. Polymorphism of cocoa butter
does not provide benefits in the case of
suppositories. This condition means that cocoa butter can very easily be overheated
and, when it is, it may solidify as one of the lower melting polymorphs. This condition
results in the production of unstable suppositories in which the suppositories are
not set up properly and might melt or liquefy when handled by the end users. In addition,
as with all fatty bases, cocoa butter suppositories may give a poor and erratic release
of certain drugs. When drugs do not have a water-soluble form, like acetaminophen,
cocoa butter should not be used as the base [61].
A study done by Chushenko et al. aimed to create cocoa butter bases for the preparation
of suppositories with various active pharmaceutical ingredients using a casting method.
The researchers concluded that the base produced in the study was well tolerated and
did not have osmotic pressure. Cocoa butter in combination with lecithin, which is
an emulsifier, has a lubricating moderate reparative action. The bases produced are
recommended by the researchers for introduction of various types of medicinal substances
such as thermolabile substances, volatile substances, enzymes and probiotics, substances
with a high melting point, and dense and liquid extracts [62].
Future Trends of Cocoa Butter
Future Trends of Cocoa Butter
Nowadays, the usage and applications of cocoa butter are not only limited to the food
industry but have been expanded to the pharmaceutical industry. The market is driven
by innovation and the introduction of new cocoa-based products as well as an increase
in the use of cocoa in cosmetics and pharmaceuticals, which is raising the demand
for chocolate [63]. Recently, cocoa butter has been further utilized in the pharmaceutical industry
due to its unique characteristics, which include a melting point close to humansʼ
body temperature. Cocoa butter acts as a lubricant, binder, delivery carrier, and
release agent in the formulations of oral dosage forms and suppositories. The pharmaceutical
industry never stops searching for novel functional excipients that offer functionalities
beyond the excipients currently available. Cocoa butter is an excipient that has huge
potential as a carrier for controlled release formulations or for enhancing
bioavailability. This condition may lead to the exploration of cocoa butterʼs application
in the pharmaceutical industry, especially lipid-based drug delivery systems.
In addition, as mentioned above, cocoa butter was applied as a solid lipid in a nano-delivery
system. With the advancement of technology, nano-delivery systems will be further
studied and developed in the future due to their advantages. Cocoa butterʼs lipid
nature allows it to be incorporated in nano-delivery systems or lipid-based formulations.
This condition may help to improve the solubility and absorption of hydrophobic drugs.
Nowadays, the public feels miserable towards healthy lifestyles, organic foods, and
ingredients. Thus, there is a growing consumer preference for natural and plant-based
ingredients. The same condition goes for pharmaceutical products. Cocoa butter, which
is extracted from the cocoa bean of T. cacao plant, meets the preferences of consumers.
In addition, research never ends in the pharmaceutical industry. Since cocoa butter
consists of various bioactive compounds and displays potential health benefits such
as antioxidants, more researchers will work together to study the potential therapeutic
benefits of cocoa butter. For example, the usage of cocoa butter can be further studied
in the areas of wound healing, dermatology, and inflammation management. The prospects
of cocoa are bright and interesting. Ongoing research in the field of nutrition and
health may result in the creation of cocoa-based products with increased health advantages,
leveraging the natural antioxidant qualities and possible mood-enhancing effects of
cocoa [63].
Conclusion
In summary, the uniqueness and properties of cocoa butter allow for the usage of cocoa
butter to be further studied and expanded, especially in the pharmaceutical industry.
The introduction of CBAs has overcome the obstacles faced in the production of cocoa
butter, such as a limited yield from the production of cocoa butterʼs source, T. cacao. In the pharmaceutical industry, cocoa butter had been used in different types of
drug delivery methods such as the nano-delivery system and the newly introduced chocolate-based
drug delivery system. Except for the food industry, cocoa butter has been studied
and applied extensively in other fields, which includes the cosmetics field, pharmaceutical
industry, and others. Researchers and professionals from various fields are studying
and working hard to amplify the benefits and uniqueness of cocoa butter when applied
in the manufacturing of various types of products.
Contributorsʼ Statement
Data collection: Y. H. Loke, H. C. Phang, N. Mohamad, P.E Kee; Design of the study:
K. B. Liew; Analysis and interpretation of the data: Y. H. Loke, H. C. Phang, N. Mohamad,
P.E Kee; Drafting the manuscript: Y. H. Loke, H. C. Phang, N. Mohamad, P.E Kee; Critical
revision of the manuscript: Y. L. Chew, S.-K. Lee, C. F. Goh, C. I. Yeo, K. B. Liew
