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Botany from Space

Sentinel 2

Sentinel-2 is a polar-orbiting, multispectral high-resolution imaging mission for land monitoring to provide, for example, imagery of vegetation, soil and water cover, inland waterways and coastal areas. ...

Sentinel 2 is sending beatiful pictures to planet earth. You can see them here:
http://www.esa.int/spaceinimages/Missions/Sentinel-2

you can read more -here-

What can Sentinel 2do?

Description: Sentinel-2 is the first optical Earth observation mission of its kind to include three bands in the ‘red edge’, which provide key information on the state of vegetation. In this image from 6 July 2015 acquired near Toulouse, France, the satellite’s multispectral instrument was able to discriminate between two types of crops: sunflower (in orange) and maize (in yellow).

source http://www.esa.int/spaceinimages/Images/2015/07/Sentinel-2_for_agriculture

More about Sentinel 2

Sentinel 2

In fact, Sentinel-2 is the first optical Earth observation mission of its kind to include three bands in the ‘red edge’, which provide key information on vegetation state.

Sentinel-2 is designed to provide images that can be used to distinguish between different crop types as well as data on numerous plant indices, such as leaf area index, leaf chlorophyll content and leaf water content – all of which are essential to accurately monitor plant growth.

This kind of information will help informed decisions to be made – whether they are about deciding how much water or fertiliser is needed for a maximum harvest or for forming strategies to address climate change.

While this has obvious economic benefits, this kind of information is also important for developing countries where food security is an issue

5. From pod to bean, different varieties of cacao & consumption

(BAILLEUX ET AL., 1995) The cacao pods grow on the trunks of the trees. Usually it is possible to see of they are ripe by looking at their colour. However, in Surinam, where the pods are almost always purplish in colour, the pickers have to identify the ripe fruit by ear. “The pods should make a dull sound when tapped lightly with the fingers, and the seeds should be distinctly heard rattling against each other.” Long poles, with a sharp blade on the end are used to remove the pods from the trees. The pods are being split and emptied by hand. Sometimes the open pods are used as fertilizers and animal feed or to make whine, brandy or cacao vinegar. Usually, they are not used at all.

The seeds have to be fermented to destroy the seed’s embryo, so it will not be able to germinate any more. Now the seed is called a bean. The fermentation process is also important for the future flavour of the chocolate. The faster the process goes, the better the cacao will be. The taste of chocolate is determined by more than five hundred different substances, which can all be identified in one single seed.

The seeds are dried in the sun on banana leaves, in special trays, or on the floor. The length of the drying period is dependent on the variety of the cacao. There are three different varieties of cacao trees; criollos, forasteros, and trinitarios. Criollo (=indigenous) trees used to be the chocolate trees of the Maya and they are also the legendary variety which was cultivated by the Aztec god Quetzacoatl. Since these trees are very delicate, have low yields, and require a lot of care, they are only used on a very small scale (less then 10 % of the world production). Criollo trees are mainly cultivated in Central- and South American countries.

The majority of the African cacao crop is produced by the forastero (=foreign) variety. These trees grow much faster and produce more fruit than the Criollos. They are responsible for 80 % of the world production. It has a strong, bitter flavour and is therefore frequently used in blends. Some people say that forastero is to chocolate what robusta is to coffee.

At the beginning of the eighteenth century, a hurricane destroyed most of the criollo trees in Trinidad, which had been planted by Spanish colonists. Because of this loss, Forasteros were planted. The intercrossings of this two varieties resulted in a new variety: the Trinitarios. These trees produce fine cacao beans with a high fat content and represent 10 to 15 % of the world production. It is now grown in several areas but the quality varies strong, depending on the region. The best Trinitarios are found on their native island, Trinidad.

When the beans are dried, they are put in sacs and transported to different countries. The consumption of cacao has grown enormously since it has been discovered (see table 2).

Nowadays, 400,000 tons of cacao per year reach Amsterdam, the largest ca¬cao port in the World. 250,000 tons are being transported as bulk in stead of in the traditional bags. This transport method saves time and money (ANEMA, 1997). The chocolate market is still growing. Japanese are also starting to eat chocolate, now it is being promoted there (Velders, 1997).

- back to index -
- chapter 4 : Cacao plantations -
- chapter 6 : Chocolate war -

6. Chocolate War

Since chocolate is big business, a lot of research is done on ways to make the production and transportation methods of cacao cheaper. One way to make chocolate cheaper is to put less cacao butter in it, and to add some cacao butter replacing fats, such as palm and soy oil. According to the chocolate producers, chocolate bars with cacao butter replacing fats also have the advantage that they do not turn white when kept for a longer period. The European Committee proposed in April 1996, that all members of the European union should decide for themselves, whether or not they allow the production of chocolate with 5% cacao butter replacing fats and that both kinds of chocolate may be sold in all the countries of the European Union, as long as the label tells us what kind of cacao butter is inside. By making this proposal, the European Committee probably forgot about the International Cacao Agreement. In 1993, all who signed this agreement, where obliged to help the cacao producing nations and to take all possible steps to stimulate the consumption of cacao in their countries.

Figure 5: Current Chocolate Laws in Europe (Fair Trade, 1997)

In some European countries "chocolate" with cacao butter substitutes is already being produced. Seven countries do not allow any cacao butter replacing fats in chocolate, but eight countries do allow a maximum of 5 % cacao butter replacing fats in their "chocolate". (see the map in figure 5)

Because of these differences between the European countries , there's a situation of unfair concurrency. For instance, English chocolate producers are allowed to make cheap chocolate with less cacao butter and sell them in the Dutch shops, while the Dutch producers of chocolate are not allowed to put cacao butter substitutes in their chocolate bars. The chocolate producers aren't very happy with this situation. Therefore the European parliament will decide on the harmonization of the chocolate laws, this month. The question is whether one should allow a maximum of 5% cacao butter replacing fats, or whether one should completely forbid the use of cacao butter substitutes.

- back to index -
- chapter 5 : From pod to bean, different varieties of cacao & consumption -
- chapter 7 : Will Chocolate Still be chocolate? -

7. Will Chocolate still be chocolate?

(FAIR TRADE, 1997) Beside the chocolate industries, the oil and fat industries also would appreciate the use of cacao butter replacing fats, which are 20% cheaper than cacao butter. The Dutch Ministry of Economic affairs favours the interests of the oil- and fat industry and is subsidizing research on enzyme technology which makes cheap oils, such as palm and soja oils, useful for replacing cacao butter.

Of course the members of the European Parliament also have to cope with other wishes, than those of the owners of chocolate factories and those of the oil and fat industries. According to a research of NIPO, 60 % of the Dutch population does not want to eat fake chocolate. The Heart Foundation is also against the use of cacao butter replacers, since they might have a bad influence on the amount of cholesterol in our blood.

The organisations "Fair Trade", "Max Havelaar", "Wereldwinkels", and the organisations which help to develop the third world (SNV and Novib), are standing up for small cacao farmers. Cacao is a cash crop for these farmers, so they are 100% dependent on it. The Minister of Foreign affairs and Jan Pronk, the minister of third world affairs, are also afraid that the use of cacao butter replacers will have a very negative effect on the income of the cacao farmers. "The trade of cacao will be diminished with 150,000 tons which means a loss of income of 450,000,000 dollars for the farmers." 

Van Aartsen, the Dutch Minister of Agriculture, is the one who is responsible for the fulfilling of the International Cacao agreement. In September 1996 he said that the Netherlands will vote against the proposal of the European Committee.

The trade union, FNV, is also against the use of fake cacao butter. They are worried about all the jobs that might disappear in the ports and the cacao industry.

- back to index -
- chapter 6 : Chocolate war -
- chapter 8 : Synthesis: From chocolatl to chocodream -

8. Synthesis

From chocolatl to chocodream 

The taste of chocolate has changed through the years. We started with spicy chocolatl and now we have sweet chocolate. Faster and cheaper chocolate production methods have been developed. This trend started by growing trees which give more fruits, but low(er) cacao qualities than the trees which were grown by the Maya and Aztecs.

It has become so popular that more and more people want to eat the food, which was once so rare that it was used as gifts for gods and kings. Nowadays it is possible to buy chocolate just until the gas station around the corner is closed. Apparently the managers of chocolate factories think that chocolate is so addictive that they can even sell us artificial chocolate.

Who knows, one day they’ll even invent cacao beanless-chocolate! Whenever this “chocodream” arrives on the shelves, I hope people will keep in mind that the real chocolate is still made out of little beans, derived from so called cacao pods which grow on real trees!

- back to index -
- chapter 7 : Will chocolate still be chocolate? -
- literature -

4. Cacao plantations

The first Spanish plantations were in Mexico in 1568. In 1660 the French planted cacao trees in Martinique. In the middle of the 18th century plantations were set up in Ecuador, Brazil, and Trinidad. In 1822 Africa got it’s first plantations. The Dutch transported the tree to Java and Sumatra, from where it spread to Sri Lanka, New Guinea, Samoa, and Indonesia. (BAILLEUX ET AL., 1995).

Figure 4; Theobroma Cacao groing under banana trees

The most important things for cacao trees are a humid atmosphere and enough shadow. This is why the trees are often grown together with other trees. For this purpose, mango-, coconut-, palm-, or lemon trees are used. Another tree, Glircidia sepium, “madre del cacao” is also often used as a sun screen (BAILLEUX ET AL., 1995). In figure 4 you can see an example of a cacao tree growing under a banana tree (COSTARICA INTERNETPAGE).


- index
- chapter 3 : The Chocolate revolution -
- chapter 5 : From pod to bean; different varieties of cacao & consumption -

The Taste of Chocolate LITERATURE

LITERATURE

-back to index-

Anema K., Nederland is een maalland (interview with L. Bensdorp, the managing director of NCV, the Dutch Cacao Society), Platform April 1997, Extern magazine over het beleidsterrein van Landbouw Natuurbeheer, en Visserij.

Capus G. & Bois D., 1912, Les produits coloniaux, Paris, Librairie Armand Colin.

Bailleux N., Bizeul H., Feltwell J., Kopp R., Kummer C., Labanne P., Pauly C., Perrard O., Schiaffino M.,1995, The book of chocolate, Translated from Le livre du chocolat, Paris-New York, Flammarion.

Dahl R. & Dahl F., 1991, Aan tafel met Roald Dahl, translated from Memories with food at Gipsy House, Baarn, Uitgeverij de Fontein. -click-

Encyclopaedia Britannica, 1967, Volume 6 “cacao”.

Fair Trade Organisatie, De Chocoslag; voor- en tegenstanders van nepchocolade, Handelskrant , April 1997

 Kusiak L., Vervangende cacaovetten schaden ons marktaandeel (interview with P. Naar, Director of Gerkens Cacao BV), Platform April 1997, Extern magazine over het beleidsterrein van Landbouw Natuurbeheer, en Visserij. 

Mabberley D.J., 1997 ed. 2., The Plant-book, Cambridge Univ. Press

Schuitemaker I., Overheid moet niet betrokken worden bij grondstoffenmarkt (interview with F. Kasbergen, chairman of NSC, the Dutch Foundation for the Chocolate Industry), Platform April 1997, Extern magazine over het beleidsterrein van Land¬bouw Natuurbeheer, en Visserij.

Veenman and sons Wageningen, 1954, Veenman’s agrarische encyclopedie voor landbouw, tuin¬bouw en bos¬bouw, Amsterdam-Brussel, Elsevier.

Velders C., Intenationale cacao overeenkomst binnenkort in de Tweede Kamer, Platform April 1997, Extern magazine over het beleidsterrein van Landbouw Natuur¬beheer, en Visserij.

Verdonk A., Het is redelijk om cacaoproducenten compensaite te geven (interview with K. Burger of the Institute of economic and social sciences, VU-Amsterdam), Platform April 1997, Extern magazine over het beleidsterrein van Landbouw Natuur¬beheer, en Visserij.

Willemsen C., Het bruine goud van de evenaar, Platform April 1997, Extern magazine over het beleidsterrein van Landbouw Natuurbeheer, en Visserij.

internetpages:
 “CostaRica”; Theobroma cacao, Musa http://www.spg.wau.nl/agro/fac serv/imbase/7000/7565.htm 8 Dec 95

 “CropSearch” Theobroma cacao Crop Index. CropSEARCH. NewCROP Homepage. Theobroma cacao L. Sterculia¬ceae Chocolate, Cacao, Cocoa. Source: James A. Duke. 1983.  Handbook of Energy Crops.. http://www.hort.purdue.edu/newcrop/duke_energy/Theobroma_cacao 4 Oct 96 

“Jamaica” Jamaican Chocolate Chocolate an Introduction. http://wwwchem.uwimona.edu.jm:1104/lectures/cocoa.html 30 Jan 97

Dahl R. & Dahl F. Memories with food at Gipsy House

Dahl R. & Dahl F., 1991, Aan tafel met Roald Dahl,
translated from Memories with food at Gipsy House, Baarn, Uitgeverij de Fontein.

3. The Chocolate revolution

The invention of Van Houten of extracting cacao butter from cacao seeds was an important step in the evolution of chocolate (Velders, 1997). In 1870, Daniel Peters and Henry Nestle, mixed cacao powder with milk and sugar and the first chocolate bar was born (Bailleux et al., 1995; Jamaica-internetpage).According to Roald Dahl (1991), the glory years of chocolate were between 1930 and 1937, as is illustrated in table 1.

 Table 1; The Glorious chocolate years (Dahl, 1991)

- back to index -

- chapter 2 : The history of cacao -

- chapter 4 : Cacao plantations -

2. The history of cacao

use of cacao by the Maya and the Aztecs

The area between the Orinoco and the Amazon river used to be the only place where the Cacao tree was growing. It was only used by small animals, who ate the tangy nutritious pulp inside the fruits. The Maya entered this area around 1000 B.C. It was probably Hunhpu, the third Maya King, who developed the cultivation of cacao. The beans were not only used to make cacao but also being used as a form of currency. Perhaps the cacao tax, which was levied on the towns by the last princess of the empire, was one of the causes of the mysterious collapse of the Maya cul­ture.

Also the Aztecs used cacao. The ‘chocolatl’ they made consisted of cacao and chili peppers. Sometimes they added medicinal plants or sweetened the drink with honey. They used the drink as a stimulant for mind and body. Not everybody used this chocolate drink, since cacao plantations were not very common. In fact, they were so rare that the beans were also used as currency and as gifts for gods and kings. “ A pump­kin cost four beans, a rabbit was worth ten, twelve were required for the services of a prostitute and one hundred for the purchase of a slave” (Bailleux et al., 1995).

Discovery of cacao by Columbus and Cortés

In 1502 Cristopher Columbus was the first who tasted some Aztec-chocolatl, but since he found the beverage very spicy and bitter, he wasn’t very interested in the sac with beans he got from the Aztecs. Hernán Cortés, who arrived in 1519, was very lucky to meet Montezuma. Montezuma believed that Cortés was a reincarnation of Quetzacoatl, who according to Aztec-legends was supposed to return from the land where the sun rises, to his native country. This was the reason why Montezuma imme­diately offered Cortés a vast plantation of cacao trees. Unlike Columbus, Cortés quickly became to understand the economic value of cacao. However, it took some years for chocolate became popular, since people still used the Aztec-recipe to prepare chocolatl.

In 1585 the first commercial cargo of cacao was unloaded in Spain. It was popular at the court and aristocratic households. It was also known in the Nether­lands and Flanders (which were part of the Spanish territories). In 1606 the chocolate was introduced in Italy, nine years later a Spanish princess brought cacao to France. In monasteries very fine chocolate-drinks recipes were developed. The chocolate drinks they made were sufficiently nourishing to provide lengthy relief from hunger pangs during the fasts. In 1657 the first English chocolate-house was opened, and many followed. In 1734 Linnaeus gave the chocolate tree the name Theobroma cacao, since it was said that chocolate, more than nectar or ambrosia, was the true food of the gods.

- back to index -

- chapter 1: The cacao tree; Theobroma cacao -
- chapter 3 : The Chocolate revolution -

1. The cacao tree; Theobroma cacao

The tree, it’s flowers, and it’s fruits

The cacao tree, Theobroma cacao (family Sterculiaceae) is a member of the order Malvales in which several ecologically and economically significant flowering plants are included. Not only cacao, but also meranti, jute, kapok and cotton are derived from plants of the order Malvales. (Mabberley, 1997)

The cacao tree is native to central and south America. Nowadays it can also be found in Africa and Malaysia. Under natural circumstances the tree may attain a height of 40 feet, but in cultivation the trees are pruned down to a height of 15 to 25 feet. It has wide growing branches with leathery -one foot long- leaves, which help to protect the flowers and the fruits against sharp sun rays. (See figure 1) In Africa and America the tree flowers at the beginning of the rainy season. In Malaysia, where there is no rainy season, the trees bear flowers all the year round. The flowers (figure 2) grow directly on the tree trunk and the large branches. When the flowers are pollinated and fertilized, cacao pods will develop. When the pods ripen they will change colour from green and yellow-orange , to reddish purple. The mature pods  resemble small rugby balls or cucumbers and are 6 to 14 inches long and 2 to 5 inches in diameter. The are very hard and woody, with five ribs. Within the pod you can find 25 to 50 almond-shaped whitish, lavender or purplish seeds which are approximately 1 inch in diameter. The seeds are imbedded in a white or pinkish mucilaginous pulp (figure 3). (Bailleux et al., 1995; Encyclopaedia Britannica, 1967)

Figure 1; Cacao with Fruits (Veenman & Sons, 1954)

Figure 2; Flower of the cacao tree  (Veenman & Sons, 1954)

Figure 3; Flower , fruits & seeds of Theobroma cacao (Velders, 1997)

The seeds are used to produce cacao, cacao butter and diverse chocolate products. The rests of the fruits can only be used as animal food, after the theobromine has been extracted.


- back to index -
- chapter 2.The history of cacao -

The Taste of Chocolate

The history of Theobroma cacao

and it’s effects on today’s economy

Anja Henseler Leiden, April 1997
(Economic Botany course,Prof. Dr. D.J. Mabberley)

1. The cacao tree; Theobroma cacao
2. The history of cacao
3. The chocolate revolution
4. Cacao plantations
5. From pod to bean, different varieties of cacao, & Consumption
6. Chocolate war
7. Will chocolate still be chocolate?
8. Synthesis
9. Literature