COCOA

The cocoa tree (Theobroma cacao) is a native of the dense tropical forests of the Amazon. The term “Theobroma” means “food of the Gods”. The word cocoa has originated from the Aztec word “Cacahuati”. Cocoa describes the bulk commercially dried, fermented beans, as well as powder from cocoa beans. The main procedures and exporters of the cocoa bean are West Africa (74% of the world production), North, Central and South Africa (21%) and Asia and Australia (3%). However the processing of the bean into chocolate is done in several other countries and some of the best chocolate is produced in Belgium, Switzerland and France.

The Cocoa Plant
The cocoa plant is a small tropical tree, originally grown in South and Central America; but now commercially grown in West Africa. The cocoa tree requires a good soil, a huge rainfall and a low altitude. The part of the plant that is processed and used for the making of cocoa and chocolate is the fruit that grows on the main trunk of the tree, as well as on the branches. The fruit is a large pod 4“ to 12“ in length and about 4“ in diameter and has a hard leathery rind containing 25-75 seeds in distinct rows, embedded in a soft pulp.

Classification
Cocoa may be classified under the following headings:
1. By the country of origin (Zambia/Mozambique).
2. By the species of the bean (Criollo/Forastero).
3. By the method of manufacture (For drinking chocolate/for milk chocolate).
4. By their particular use (Vending machines/Icings/Chocolate moulding).

Processing of Cocoa
The processing of cocoa bean into cocoa powder is done in seven stages, as mentioned under:
1. Fermentation of the Beans
The ripe cocoa pods are collected and split open and the beans and the pulp surrounding them are scooped out and put into a fermentation chamber, also called the sweat boxes, where the temperature is allowed to rise to 40 to 50°C (104 to 122°F). Fermentation will kill the germs and prevent germination and decomposition of the bean. It will also encourage enzyme reaction reducing the bitterness and developing flavour. The beans absorb the liquid from the fermenting sugary pulp which will then turn into alcohol and finally into acetic acid. As soon as the mass turns into the acid state, the fermentation is stopped. Otherwise unpleasant flavours and odours will develop.
2. Drying of the Beans
This is done by laying the beans thinly out in the Sun to dry and occasionally turning them over, or by passing them through a mechanical drying chamber. When completely dried, there will not be more than 4% moisture in the bean. At this stage, beans are exported, unless they are to be processed into cocoa chocolate.
3. Roasting the Beans
This stage is essential to develop the flavour and the aroma of the bean and to give colour. Moisture is lost at the stage, which assists in the removal of the shell from the beans.
4. Removing the Shell
This stage is also called “Winnowing”. The shell is removed from the bean by passing them through a series of rollers and sieves. The de-shelled beans, now mostly broken bits and pieces, are referred to as “Nibs”.
5. Alkalization of the Nibs (Dutch Processing)
This stage, that further develops the flavour and colour, is usually done by tumbling the nibs in an alkali solution. After drying, the nibs may be roasted to correct the moisture content.
6. Grinding the nibs
The nibs are now ground into very small particles, a process which releases a large amount of fat and results in the mass becoming a thick syrup. This fat is known as “Cocoa Butter”, usually 50% of the nibs.
7. Extraction of the Cocoa Butter
The cocoa fluid/mass is then fed into large felt lined steel pans fitted with a movable perforated lid. When subjected to hydraulic pressure, some of the fat is forced through the filter cloths, leaving behind a solid residue, known as the “Press Cake”. This is removed from the pan, allowed to cool, then pulverized and sieved. TO this fine powder, a small amount of salt and vanilla is usually added before it is marketed as the popular cocoa powder.

Plain Chocolate
The processing of chocolate involves the first six stages as for the processing of cocoa and then a further three stages:
1. Mixing the Cocoa mass with sugar
The cocoa mass is thoroughly mixed with powdered sugar in large blending kettles. The fat content is strictly controlled to obtain a standard product. Additional cocoa butter may be added to adjust the consistency.
2. Refining the mixture
This is done by passing the mixture through a series of five heavy rollers to reduce the size of the non-fat particles, so that the chocolate will be smooth to the palate. This stage exposes the particles to the air, reducing the moisture content, partially evaporating volatile substances, and lightening the colour of the mixture.
3. Conching
The final stage is concerned with producing a standard quality of chocolate. Conching is the mechanical agitation of the chocolate mass with additional cocoa butter at a temperature of 60-70°C (140-158°F). This will further evaporate volatile substances and also develop the flavour. Additional flavourings may also be added at this stage and the mixture is standardized. The chocolate is then set in moulds such as bars, slabs and is also known as courverture.
A chocolate in block has a tendency to collect moisture from the air and this can be seen in the form of beads of perspiration. This could be wiped carefully and well scraped before being used for dipping.

Milk Chocolate
The processing of milk chocolate is the same as Plain Chocolate (courverture), except that milk crumb is added at the refining stage and the conching is done at a lower temperature, but for a longer time. Milk crumb is a mixture of condensed milk and chocolate mass, reduced to a powder form.

Cocoa Powder
It is a product obtained by grinding roasted cocoa beans to an oily liquid, pressing this in a cocoa-butter press, to remove about half cocoa butter and then grinding the residual press cake to a powder. Chocolate powder is a blend of true cocoa powder, sugar and starch.

Drinking Chocolate
It is a modern beverage drink, prepared from the chocolate powder or chocolate flakes and made in similar manner to the cocoa drink, by adding hot water or milk.

White Chocolate
It is a product composed of pure cocoa butter, full of cream milk powder and sugar, milled together and passed through refining rolls. As pure cocoa butter has a strong taste and odour of chocolate, the product is similar in flavour to chocolate. It can be tempered and molded. Provided fat-soluble edible colours are used, white chocolate can be coloured pink, orange, yellow or green.

Chocolate Spread
It is permanently soft, pasty or semi-liquid product, which can be used in bakery as flavouring and colouring material for fillings, butter creams and fondants. To make it, add warmed golden syrup to melted chocolate courverture in the proportion of two parts of syrup to one part of courverture, mixing them thoroughly and adding the warm syrup into glass or glazed earthen ware jars and kept for use as needed.

Panache
It is the name given to a blend of chocolate and cream. Boiling fresh cream is mixed with grated or melted courverture and stirred occasionally till cooled.

Composition of Cocoa and Chocolate
Theobromine is the stimulant in cocoa and chocolate, along with some caffeine. The other major constituents of cocoa and chocolate include colour and flavour compounds, lipids and carbohydrate. The purple colour is due to the presence of anthocyanins. The chocolate flavour is contributed by the phenolic compounds.
Starch is the chief carbohydrate in cocoa and chocolate and functions as a thickening agent. Cocoa contains 11% starch while chocolate contains 8%. Cocoa has more thickening power than chocolate because of its high starch content. For this very reason, cocoa is not substituted on a direct weight basis for chocolate. Usually 3-3.5 tablespoon of cocoa powder plus ½ table spoon of fat are considered equivalent to 30 Gms of chocolate.
Fat constituent of cocoa and chocolate is cocoa butter. Cocoa varies in fat content from 10-22%. Chocolate contains 50% fat. The low melting temperature of chocolate (near 32°C) imparts a smooth texture and readily releases flavour components.

Uses of Chocolate
Cocoa powder and Chocolate powder are used:
1. As a hot beverage.
2. AS a flavouring agent.
3. As a colouring agent.
4. For hot and cold sauces.

Courverture is used:
1. As a coating.
2. As a decoration (Piping).
3. For moulding into Easter eggs etc.
4. For sauces.
5. For ice-creams.

Storage
Cocoa and chocolate deteriorate quickly in the presence of moisture and heat. Cocoa becomes grayish in colour and lumpy when stored at temperature above 16-21°C and in high humidity.
A mottled or grey surface known as bloom may develop on the chocolate when it is exposed to high heat and moisture. The melting fat and re-crystallizing in a different pattern on the surface contribute to the formation of bloom.
Appropriate tempering procedures during processing and the use of stabilizers retards the development of bloom. Sugar bloom, a rough greyish layer, may develop on sweet chocolate due to moisture; the dissolved sugar re-crystallizes on the surface.
The chocolate flavour appears not to be altered by the development of bloom or lumping of cocoa products, but the texture may be grainy. Milk chocolates also absorb flavours and odours when stored improperly. The quality of cocoa and chocolate is best when high temperature and humidity is avoided. The best protection is tightly sealed containers kept in a cool, dry place.

Nutritional Aspect
Cocoa powder and milk chocolate are rich in fats and carbohydrates. Being a highly palatable and energy concentrated food, it was used extensively in emergency situations such as wars and during rescue and evacuation situations.

Chocolate Tempering
Chocolate tempering is a process used to prepare pure chocolate liquor for cooking purposes. During tempering, it is essential that not one drop of water should come into contact with the chocolate

Procedure
Break chocolate into small pieces and place it in a bowl over hot water. Stir occasionally until it is melted and the temperature is 46-48°C If this temperature is exceeded, the chocolate is ruined.
Remove the bowl from saucepan and set in iced water, stirring carefully until the chocolate begins to set on the bottom. Then warm the chocolate carefully over hot water until the temperature is dark chocolate to 31°C, in milk chocolate to 29°C and in white chocolate to 29°C. If the temperatures are exceeded, the tempering process should begin again.
It is only necessary to temper chocolate when using it for moulding or dipping. For any fillings, pure chocolate or cooking chocolate can be used without tempering.