Cocoa bean

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Cocoa pods in various stages of ripening

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The cocoa bean, also cacao bean[1] or simply cocoa (/ˈk.k/) or cacao (/kəˈk/), is the dried and fully fermented fatty seed of Theobroma cacao, from which cocoa solids and cocoa butter are extracted.[2] They are the basis of chocolate, as well as many Mesoamerican foods such as mole and tejate.

Etymology

Aztec sculpture with cocoa pod

The word "cocoa"' derives [3] from the Spanish word cacao, derived from the Nahuatl word cacahuatl.[4] The Nahautl word, in turn, ultimately derives from the reconstructed Proto Mije-Sokean word *kakaw~*kakawa.[5]

Cocoa can often also refer to the drink commonly known as hot chocolate;[6] to cocoa powder, the dry powder made by grinding cocoa seeds and removing the cocoa butter from the dark, bitter cocoa solids; or to a mixture of cocoa powder and cocoa butter.[7][8]

History

The cacao tree is native to the Americas. It may have originated in the foothills of the Andes in the Amazon and Orinoco basins of South America, current-day Colombia and Venezuela, where today, examples of wild cacao still can be found. However, it may have had a larger range in the past, evidence for which may be obscured because of its cultivation in these areas long before, as well as after, the Spanish arrived. New chemical analyses of residues extracted from pottery excavated at an archaeological site at Puerto Escondido in Honduras indicate cocoa products were first consumed there between 1400 and 1500 BC. The new evidence also indicates that, long before the flavor of the cacao seed (or bean) became popular, the sweet pulp of the chocolate fruit, used in making a fermented (5% alcohol) beverage, first drew attention to the plant in the Americas.[9] The cocoa bean was a common currency throughout Mesoamerica before the Spanish conquest.[10]

Cacao trees grow in a limited geographical zone, of about 20° to the north and south of the Equator. Nearly 70% of the world crop today is grown in West Africa. The cacao plant was first given its botanical name by Swedish natural scientist Carl Linnaeus in his original classification of the plant kingdom, who called it Theobroma ("food of the gods") cacao.

Cocoa was an important commodity in pre-Columbian Mesoamerica. A Spanish soldier who was part of the conquest of Mexico by Hernán Cortés tells that when Moctezuma II, emperor of the Aztecs, dined, he took no other beverage than chocolate, served in a golden goblet. Flavored with vanilla or other spices, his chocolate was whipped into a froth that dissolved in the mouth. No fewer than 60 portions each day reportedly may have been consumed by Moctezuma II, and 2,000 more by the nobles of his court.[11]

Chocolate was introduced to Europe by the Spaniards, and became a popular beverage by the mid-17th century.[12] They also introduced the cacao tree into the West Indies and the Philippines. It was also introduced into the rest of Asia and into West Africa by Europeans. In the Gold Coast, modern Ghana, cacao was introduced by an African, Tetteh Quarshie.

Production

Cocoa beans in a freshly cut cocoa pod

Cocoa pod

A cocoa pod (fruit) has a rough, leathery rind about 2 to 3 cm (0.79 to 1.18 in) thick (this varies with the origin and variety of pod) filled with sweet, mucilaginous pulp (called baba de cacao in South America) with a lemonade-like taste enclosing 30 to 50 large seeds that are fairly soft and a pale lavender to dark brownish purple color. Due to heat buildup in the fermentation process, cacao beans lose most of the purplish hue and become mostly brown in color, with an adhered skin which includes the dried remains of the fruity pulp. This skin is released easily after roasting by winnowing. White seeds are found in some rare varieties, usually mixed with purples, and are considered of higher value.[13][14][15] Historically, white cacao was cultivated by the Rama people of Nicaragua.[16]

Varieties

Three main varieties of cocoa: Criollo, Trinitario and Forastero

The three main varieties of cocoa plant are Forastero, Criollo, and Trinitario. The first is the most widely used, comprising 95% of the world production of cocoa. Cocoa beans of the Criollo variety are rarer and considered a delicacy.[17] Criollo plantations have lower yields than those of Forastero, and also tend to be less resistant to several diseases that attack the cocoa plant, hence very few countries still produce it. One of the largest producers of Criollo beans is Venezuela (Chuao and Porcelana). Trinitario (from Trinidad) is a hybrid between Criollo and Forastero varieties. It is considered to be of much higher quality than Forastero, but has higher yields and is more resistant to disease than Criollo.

Harvesting

Cocoa trees grow in hot, rainy tropical areas within 20° of latitude from the Equator.[18] Cocoa harvest is not restricted to one period per year and a harvest typically occurs over several months. In fact, in many countries, cocoa can be harvested at any time of the year.[19] Pesticides are often applied to the trees to combat capsid bugs and fungicides to fight black pod disease.[20]

Immature cocoa pods have a variety of colours, but most often are green, red, or purple, and as they mature, their colour tends towards yellow or orange, particularly in the creases.[19][21] Unlike most fruiting trees, the cacoa pod grows directly from the trunk or large branch of a tree rather than from the end of a branch, similar to jackfruit. This makes harvesting by hand easier as most of the pods will not be up in the higher branches. The pods on a tree do not ripen together; harvesting needs to be done periodically through the year.[19] Harvesting occurs between three and four times weekly during the harvest season.[19] The ripe and near-ripe pods, as judged by their colour, are harvested from the trunk and branches of the cocoa tree with a curved knife on a long pole. Care must be used when cutting the stem of the pod to avoid damaging the junction of the stem with the tree, as this is where future flowers and pods will emerge.[19][22] One person can harvest an estimated 650 pods per day.[20][23]

Harvest processing

The harvested pods are opened, typically with a machete, to expose the beans.[19][20] The pulp and cocoa seeds are removed and the rind is discarded. The pulp and seeds are then piled in heaps, placed in bins, or laid out on grates for several days. During this time, the seeds and pulp undergo "sweating", where the thick pulp liquefies as it ferments. The fermented pulp trickles away, leaving cocoa seeds behind to be collected. Sweating is important[24] for the quality of the beans, which originally have a strong, bitter taste. If sweating is interrupted, the resulting cocoa may be ruined; if underdone, the cocoa seed maintains a flavor similar to raw potatoes and becomes susceptible to mildew. Some cocoa-producing countries distill alcoholic spirits using the liquefied pulp.[25]

A typical pod contains 20 to 50 beans[18] and about 400 dried beans are required to make one pound - or 880 per kilogram - of chocolate.[18] Cocoa pods weigh an average of 400 g (0.88 lb) and each one yields 35 to 40 g (1.2 to 1.4 oz) dried beans (this yield is 40–44% of the total weight in the pod).[20] One person can separate the beans from about 2000 pods per day.[20][23]

Cocoa beans drying in the sun

The wet beans are then transported to a facility so they can be fermented and dried.[20] They are fermented for four to seven days and must be mixed every two days.[20][23] They are dried for five to 14 days, depending on the climate conditions.[20][23] The fermented beans are dried by spreading them out over a large surface and constantly raking them. In large plantations, this is done on huge trays under the sun or by using artificial heat. Small plantations may dry their harvest on little trays or on cowhides. Finally, the beans are trodden and shuffled about (often using bare human feet) and sometimes, during this process, red clay mixed with water is sprinkled over the beans to obtain a finer color, polish, and protection against molds during shipment to factories in the United States, the Netherlands, the United Kingdom, and other countries. Drying in the sun is preferable to drying by artificial means, as no extraneous flavors such as smoke or oil are introduced which might otherwise taint the flavor.

The beans should be dry for shipment (usually by sea). Traditionally exported in jute bags, over the last decade, beans are increasingly shipped in "mega-bulk" parcels of several thousand tonnes at a time on ships, or in smaller lots around 25 tonnes in 20-ft containers. Shipping in bulk significantly reduces handling costs; shipment in bags, however, either in a ship's hold or in containers, is still common.

Throughout Mesoamerica where they are native, cocoa beans are used for a variety of foods. The harvested and fermented beans may be ground to-order at tiendas de chocolate, or chocolate mills. At these mills, the cocoa can be mixed with a variety of ingredients such as cinnamon, chili peppers, almonds, vanilla, and other spices to create drinking chocolate.[26] The ground cocoa is also an important ingredient in tejate and a number of savory foods, such as mole.

World production

Top Cocoa Beans producers
in 2012
(million metric tons)
 Ivory Coast 1.650
 Indonesia 0.936
 Ghana 0.879
 Nigeria 0.383
 Cameroon 0.256
 Brazil 0.253
 Ecuador 0.133
 Mexico 0.083
 Dominican Republic 0.072
 Peru 0.057
World total 4.928
Source:
UN Food & Agriculture Organisation
(FAO)
[2]
Cocoa bean output in 2012

Nearly 5,000,000 tonnes (4,900,000 long tons; 5,500,000 short tons) of cocoa are produced each year.

The historical global production was

1974: 1,556,484 tons,
1984: 1,810,611 tons,
1994: 2,672,173 tons,
2004: 3,607,052 tons.[citation needed]

The production increased by 131.7% in 30 years, representing a compound annual growth rate of 2.9%.

About 3.54 million tonnes of cocoa beans were produced in the 2008–2009 growing year,[18] which runs from October to September.[27] Of this total, African nations produced 2.45 million tonnes (69%), Asia and Oceania produced 0.61 million tonnes (17%), and the Americas produced 0.48 million tonnes (14%).[18] Two African nations, Ivory Coast and Ghana, produce more than half of the world's cocoa, with 1.23 and 0.73 million tonnes, respectively (35% and 21%, respectively).[18]

Consumption

Different metrics are used for chocolate consumption. The Netherlands has the highest monetary amount of cocoa bean imports (US$2.1 billion); it is also one of the main ports into Europe.[18] The United States has highest amount of cocoa powder imports ($220 million); the US has a large amount of cocoa complementary products.[18] The United Kingdom has the highest amount of retail chocolate ($1.3 billion) and is one of the biggest chocolate consumption-per-capita markets.[18]

Cocoa and its products (including chocolate) are used worldwide. Per capita consumption is poorly understood, with numerous countries claiming the highest: various reports state that Switzerland, Belgium, and the UK have the highest consumption. However, since no clear mechanism exists to determine how much of a country's production is consumed by residents and how much by visitors, any data with respect to consumption remain purely speculative.

Chocolate production

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A roasted cocoa bean, the papery skin rubbed loose

To make 1 kg (2.2 lb) of chocolate, about 300 to 600 beans are processed, depending on the desired cocoa content. In a factory, the beans are roasted. Next, they are cracked and then deshelled by a "winnower". The resulting pieces of beans are called nibs. They are sometimes sold in small packages at specialty stores and markets to be used in cooking, snacking, and chocolate dishes. Since nibs are directly from the cocoa tree, they contain high amounts of theobromine. Most nibs are ground, using various methods, into a thick, creamy paste, known as chocolate liquor or cocoa paste. This "liquor" is then further processed into chocolate by mixing in (more) cocoa butter and sugar (and sometimes vanilla and lecithin as an emulsifier), and then refined, conched and tempered. Alternatively, it can be separated into cocoa powder and cocoa butter using a hydraulic press or the Broma process. This process produces around 50% cocoa butter and 50% cocoa powder. Standard cocoa powder has a fat content around 10–12%%. Cocoa butter is used in chocolate bar manufacture, other confectionery, soaps, and cosmetics.

Treating with alkali produces Dutch-process cocoa powder, which is less acidic, darker, and more mellow in flavor than what is generally available in most of the world. Regular (nonalkalized) cocoa is acidic, so when cocoa is treated with an alkaline ingredient, generally potassium carbonate, the pH increases.[28] This process can be done at various stages during manufacturing, including during nib treatment, liquor treatment, or press cake treatment.

Another process that helps develop the flavor is roasting, which can be done on the whole bean before shelling or on the nib after shelling. The time and temperature of the roast affect the result: A "low roast" produces a more acid, aromatic flavor, while a high roast gives a more intense, bitter flavor lacking complex flavor notes.[29]

Health benefits of cocoa consumption

Chocolate

In general, cocoa is considered to be a rich source of antioxidants such as procyanidins and flavanoids, which may impart antiaging properties.[2][30] Cocoa also contain a high level of flavonoids, specifically epicatechin, which may have beneficial cardiovascular effects on health.[31][32][33]

The stimulant activity of cocoa comes from the compound theobromine which is less diuretic as compared to theophylline found in tea.[2] Prolonged intake of flavanol-rich cocoa has been linked to cardiovascular health benefits,[31][32][34] though this refers to raw cocoa and to a lesser extent, dark chocolate, since flavonoids degrade during cooking and alkalizing processes.[35] Short-term benefits in LDL cholesterol levels from dark chocolate consumption have been found.[36] The addition of whole milk to milk chocolate reduces the overall cocoa content per ounce while increasing saturated fat levels.[citation needed] Although one study[37] has concluded that milk impairs the absorption of polyphenolic flavonoids, e.g. epicatechin, a followup[38] failed to find the effect.

Hollenberg and colleagues of Harvard Medical School studied the effects of cocoa and flavanols on Panama's Kuna people, who are heavy consumers of cocoa. The researchers found that the Kuna people living on the islands had significantly lower rates of heart disease and cancer compared to those on the mainland who do not drink cocoa as on the islands. It is believed that the improved blood flow after consumption of flavanol-rich cocoa may help to achieve health benefits in hearts and other organs. In particular, the benefits may extend to the brain and have important implications for learning and memory.[39][40][41][42]

Foods rich in cocoa appear to reduce blood pressure but drinking green and black tea may not, according to an analysis of previously published research in the April 9, 2007 issue of Archives of Internal Medicine[31][43]

A 15-year study of elderly men[44] published in the Archives of Internal Medicine in 2006 found a 50 percent reduction in cardiovascular mortality and a 47 percent reduction in all-cause mortality for the men regularly consuming the most cocoa, compared to those consuming the least cocoa from all sources.

Child labor

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The first allegations that child slavery is used in cocoa production appeared in 1998.[45] In late 2000, a BBC documentary reported the use of enslaved children in the production of cocoa in West Africa.[45][46][47] Other media followed by reporting widespread child slavery and child trafficking in the production of cocoa.[48][49] According to a report by the International Labour Organization (ILO), in 2002, more than 109,000 children were working on cocoa farms in Ivory Coast, some of them in "the worst forms of child labour".[50] The ILO later reported that 200,000 children were working in the cocoa industry in Ivory Coast in 2005.[51] The 2005 ILO report failed to fully characterize this problem, but estimated that up to 6% of the 200,000 children involved in cocoa production could be victims of human trafficking or slavery.[51] The cocoa industry was accused of profiting from child slavery and trafficking.[52] The Harkin-Engel protocol is an effort to end these practices.[53] It was signed and witnessed by the heads of eight major chocolate companies, Harkin, Engel, US Senator Herb Kohl, the ambassador of the Ivory Coast, the director of the International Programme on the Elimination of Child Labor, and others.[53] It has, however, been criticized by some groups including the International Labor Rights Forum as an industry initiative which falls short.[54][55][56]

Fairtrade

  • Fair trade cocoa producer groups are established in Belize, Bolivia, Cameroon, the Congo,[57] Costa Rica, the Dominican Republic,[58] Ecuador, Ghana, Haiti, India, Ivory Coast, Nicaragua, Panama, Peru, Sierra Leone, and Sao Tome and Principe.
  • As of 2014, less than 1% of the chocolate market was fair trade.[59]
  • Cadbury, one of the world's largest chocolate companies, has begun certifying its Dairy Milk bars as fair trade; according to Cadbury, in 2010 "around one quarter of ... global sales" of these bars will be fair trade.[60]

Environmental impact

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The relative poverty of many cocoa farmers means that environmental consequences such as deforestation are given little significance. For decades, cocoa farmers have encroached on virgin forest, mostly after the felling of trees by logging companies. This trend has decreased as many governments and communities are beginning to protect their remaining forested zones.[citation needed] In general, the use of chemical fertilizers and pesticides by cocoa farmers is limited. When cocoa bean prices are high, farmers may invest in their crops, leading to higher yields which, in turn tends to result in lower market prices and a renewed period of lower investment.

Cocoa production is likely to be affected in various ways by the expected effects of global warming. Specific concerns have been raised concerning its future as a cash crop in West Africa, the current centre of global cocoa production. If temperatures continue to rise, West Africa could simply become unfit to grow the beans.[61][62]

Agroforestry

Cocoa beans may be cultivated under shaded conditions, e.g. agroforestry. Agroforestry can reduce the pressure on existing protected forests for resources, such as firewood, and conserve biodiversity.[63] Agroforests act as buffers to formally protected forests and biodiversity island refuges in an open, human-dominated landscape. Research of their shade-grown coffee counterparts has shown that greater canopy cover in plots is significantly associated to greater mammal species richness and abundance.[64] The amount of diversity in tree species is fairly comparable between shade-grown cocoa plots and primary forests.[65] Farmers can grow a variety of fruit-bearing shade trees to supplement their income to help cope with the volatile cocoa prices.[66] Though cocoa has been adapted to grow under a dense rainforest canopy, agroforestry does not significantly further enhance cocoa productivity.[67]

Cocoa trading

Cocoa beans, cocoa butter and cocoa powder are traded on two world exchanges: ICE Futures U.S. and NYSE Liffe Futures and Options. The London market is based on West African cocoa and New York on cocoa predominantly from Southeast Asia. Cocoa is the world's smallest soft commodity market.

The future price of cocoa butter and cocoa powder is determined by multiplying the bean price by a ratio. The combined butter and powder ratio has tended to be around 3.5. If the combined ratio falls below 3.2 or so, production ceases to be economically viable and some factories cease extraction of butter and powder and trade exclusively in cocoa liquor.

Cocoa beans can be held in storage for several years in bags or in bulk, during which the ownership can change several times, as the cocoa is traded much the same as metal or other commodities, to gain profit for the owner.

See also

References

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External links