TheChocPro | Cacao Tree Species

While cacao has been used as a food product by Mezoamerican peoples for over 3000 years, the "chocolate bar" has only been around since the 1850's. Before that chocolate was enjoyed primarily as a beverage. There are over 80 different varieties of cacao trees used for making chocolate. Like apples, or wine grapes they all have their own unique flavour profile and some are far superior to others. 

The genetic relationships of modern cacaos are tangled. Only through DNA sequencing can we reliably tell the parentage of most trees on a plantation. Pod size, shape and colour, plus bean shape and bean colour gives us some indication but often they are only guesses. The natural promiscuity of the cacao tree does not help matters. Cross-pollination can and does occur with great regularity so a tree might bear 20 or 30 fruits at a time but as many as half of them may have been fertilized by a neighbouring tree, perhaps of not the same species at all. Grafting from a mother tree is a way to preserve the genetic purity of a line, but most cacao has historically been grown from seed. Very, very promiscuous seed....

In the wild there exist over 40 sub-species of Theobroma, most of which are unsuitable for making chocolate. In parts of South and Central America they are still used today as a tasty tree fruit snack, as a base for fermented liquors and as a source of potent pure alcohol, as a hollowed out vessel for drinking from and as an impromptu football for young boys to play with.

Traditionally cacao writers have referred to four main “families” of trees but modern reasearchers are discovering that the cacao world is far more complex than originally thought. We'll use those terms here as a starting point.

The Criollo branch encompasses those trees thought to be original to the Mayan and Aztec world. Of course these are all the products of thousands of years of Mesoamerican breeding so calling them “pure” cacao is a bit of a stretch. Wild “criollo” cacao does exist and it is generally unsuitable for chocolate making so the Olmecs and Mayans must have known a thing or two about plant genetics to turn them into the trees we now call Criollo. Most of the world's remaining stock can be found in a few areas of Venezuela, Peru and the Yucatan Peninsula in Mexico. Criollo trees were brought to Madagascar, Indonesia and Malaysia as trial plantings over the years but very few remain. Classic regions where one can expect to find pure Criollo – or something close to it – include the fabled Chuao village as well as Cayagua and Ocumare valleys in Venezuela. Guasare and Chorini are also classic Venezuelan sites but little seen today. More readily available is the Criollo variety known as Porcelana. It originated around Lake Maricaibo and has been successfully grown for centuries in Piura Valley in Peru and in the Soconusco region of Mexico. About 3% of the world's cacao trees are thought to be mostly criollo.

The Forastero group of trees originated in Brazil and were introduced to the cacao producing areas of the upper Amazon, Mexico, Central America and the Carribean during the late 1700's. A blight had affected many of the classic cacao plantations and growers were searching about for an alternative to their now suddenly susceptible criollo trees. The Brazilian trees, primarily of a group known as Amelonados, were introduced and proved hardy, disease resistant and more generous yielders than the temperamental criollo.When cacao production shifted to Africa and south east Asia in the late 1700's it was the Brazilian tree, the foreigner, or “Forastero”, which was taken along for the journey. Today it is the workhorse of the cacao industry, accounting for about 90% of the cacao trees on Earth.

The Trinitario family came about when the Brazilian Amelonado and some mainland criollo were brought to the island of Trinidad after its native criollos were devestated by a fungal disease in 1727. The remaining criollos quickly interbred with the new trees creating a hybrid that was distinctly different. Hardier than criollo but with many of its aromatic complexities. A prominent citrus-red berry note developed in the flavour of the beans over time and Trinitario became a popular tree among growers from Madagascar to New Guinea. Not all crosses of Criollo and Amelonado will produce a Trinitario however. Only those criollo trees already growing on the island of Trinidad in the 1700's had the right genetic make-up to produce this tree and they no longer exist. True Trinitario now is carefully reproduced in nurseries by grafting trees which can trace their lineage back to the original sources. Trinitario trees make up about 7% of the world's cacao plantings.

There is a fourth “branch” of the cacao tree which is found only in Ecuador and Peru – the Nacional tree. It has been classed as a Forastero because visually it appears much more like them than any other tree, but really it should be considered among the Criollo group. This tree developed along a different evolutionary path than did the criollos of Venezuela and was farmed by the Incas and their ancestors for thousands of years in the jungles of the Andes. Unfortunately, like much of the original criollo plantings, the stock has been completely adulterated over time. Almost every plantation in Ecuador grows what it claims to be pure Nacional and almost every one in fact grows a melange of Forastero from Brazil, Trinitario from Bolivia and Columbia and some original Nacional that has crossed freely with these other trees over hundreds of years. Hardly a pure genetic sampling. Some growers in Ecuador tout their own Nacional strain called “Arriba” as the superior one but true Arriba is a very rare bean indeed. Some describe the taste of Nacional as “flowery, smooth, and exotically spicy”. While very little Ecuadorean chocolate would fall under this heading today, it is a moot point as no one has tasted pure Nacional in years. Occasionally a tree is discovered in Ecuador or Peru which tests true for the DNA signature of Nacional and much excitement ensues in the press. Work is being done to propogate the true strain and bring it to market but so far no one has done so in any commercial quantity. Still, we group the cacao trees in Ecuador which are not clearly Amelonado crosses or Trinitario descendants as “Criollo/Arriba” and include them in the 3% quoted above.

So where does this leave the puzzled chocolate lover looking for the good stuff? Sadly virtually all the research dollars going into the cacao industry today (and we're talking billions here) are focussed on two areas: disease resistance and yield. Rare, ancient species of trees are being lost daily as growers cut them down to make way for easier to grow, hardier stock that produce a far larger crop. The one element that no one seems to be talking about at all is flavour. Hundreds of new clones and crossings are produced at cacao research stations every year but very few are grown in any quantity that they produce enough beans to make a chocolate bar out of.

At places like the Chama Research Station in Venezuela and the International Cacao Genebank in Trinidad there are positive developments pointing the way for the future of fine cacao. Trees are field tested in the wild and beans are harvested, fermented and processed into chocolate. Occasionally a bag of beans from a particularly successful variety will find their way to a chocolate maker for further experimentation. Seedlings from these and other rare genotype nurseries are slowly making their way into the fields of actual cacao farmers, where they will become the mother trees for future generations.

We're not out of the woods yet and since fine, or “flavour” cacao comprises less than 10% of world production it could be considered an endangered crop. Will it be around for future generations to enjoy? Only if chocolate lovers insist on buying it and nothing else.