Cacao – exotic, fussy and downright picky

My first public talk on chocolate was back in 2003 at the Natural History Museum. I was based there as a PhD student, researching and analysing the recorded data of the 800 or so medicinal plants used in homeopathy. Those were great years and I shared the botany students room together with 2 other PhD students, who were also registered at the University of Reading. We were supervised jointly by the museum scientists and those at Reading, and made good use of the renowned herbaria and the specialist libraries. Having access to the many rare books, maps, manuscripts, original drawings and paintings from the different expeditions like Cook’s voyages and many others were an added bonus.

Our room on the mezzanine level above the cryptogamic herbarium had a huge expanse of glass skylight and this was home to us as we toiled towards our theses. The student room was close to the common room and here we met, ate, drank, discussed, thrashed out ideas and picked the brains of the scientists, researchers and curators who worked there. There are around 350 scientists, beavering away behind the scenes, in offices most often hidden away in the nooks and crannies of this terracotta clad steel framed building.

The Natural History Museum with its twin towers on either side marking its entrance. Image © John Hunnex

As part of the PhD process, I had to give a number of seminars both within and outside the museum and was also encouraged to do some public speaking. Around this time there was a lot of press coverage about whether chocolate was good for us especially dark chocolate. As Theobroma cacao was one of the medicinal plants I had researched, I wanted to touch base with my childhood memories of the cacao pods I had seen In Zanzibar and talk about my findings about this plant. Having lived in Africa, India and now Britain, and as many of the medicinal plants I had researched were also food plants, I started giving public talks on the plants we eat at the museum and other places.

The scene opens at the foothills of the Andes in Venezuela. Here around the Orinoco basin of the Amazonian equatorial forest, the floor is littered with dead leaves, moss, and fern covered twigs and logs. All around are plants, from the small and spindly understory trees to the tall and majestic jungle canopy, which stretches like a huge parasol. The steamy air is filled with the smell of damp vegetation and the relentless goings on of insects, birds and animals, both visible and invisible. This is believed to be where the wild cacao trees grew.

But the early history of cacao cultivation remains a mystery, with many believing the Aztecs to be the first to develop this ancient flavour. However, the word cacao is Mayan from Central America. Analysis of residue from a ceramic ‘teapot’, suggests that the Maya and their ancestors may have gobbled chocolate, as far back as the Olmec civilization some 3,000 years ago.

With its exacting temperature, moisture and soil requirements, this exotic plant now circles around the globe and includes many cultures. But it is downright picky and fussy as to where it lives, thriving almost exclusively, within the narrow tropical belt of 15 to 20 degrees north and south of the equator.

The chocolate belt – 15 to 20 degrees north and south of the equator

Unlike most trees where the flowers appear at branch tips, the cacao flowers appear on cushion like pads on the trunk and bigger branches. Just imagine, thousands of these tiny, star-shaped, white, pink or yellow flowers, popping straight out of the trunk. Now flowers need pollinators to form the fruits, and true to its nature, the fussy cacao has very picky pollinators. These are very tiny midge like insects that only breed in the rotting jungle vegetation around these trees and only manage to pollinate around 5% of the flowers. I saw a specimen of one these species – the Forcipomyia midge in the entomology collection at the Natural history Museum and this one was tiny!
The pods when produced, as you have seen in the earlier post, hang downwards from the trunk and fattest branches and remind me of goat udders, ok, maybe not the colour. Six to twelve inches long, their shape can vary from udder like, to rounded like a rugby ball to narrow and pointed, or deeply ridged and warty. In shades of green, red, purple or maroon when unripe to yellow or orange when ripe these pods are indeed unusual.

Picked cacao pods transported in style

I am sorry to sound so enthusiastic about these pods, after all they are just pods like many other pods with seeds inside them, big deal, ah! but what a cargo these pods carry. And even the texture varies from smooth to ridged and warty. Just looking around at the vegetables and fruits, trees and leaves, I always wonder why we buy those funny little dangly things made of different materials for children to experience textures when we can just let them look, touch, feel and smell our kitchen fruits and vegetables. But then, it would not look good would it, a carrot, cabbage leaf, beans or broccoli all strung up on one side of the pram.

Harvested heap of ripe cacao pods in Ambanja, Madagascar

Chocolate making starts in the field with the dumped heap of harvested pods. The pods are split open with a specialised machete which has a ridge so it does not go right through and injure the gooey pulp with the beans inside it. This is still done manually and is a slow and laborious job.

Breaking open the cacao pods. The husks are left in piles where they rot and become breeding sites for a variety of insects, including potential pollinators.

The soft white pulp enclosing the beans are scooped out and the membranes that hold the cacao beans together in the pod, removed.

Removing the membranes that hold the cacao beans in the pod by running fingers through the satiny white pulp

This pulp is then fermented from a few days for the Criollo and Trinitario variety of beans, to up to a week for the bitter and astringent Forastero. This is done by heaping the pulp on banana leaves and covering them with more of these leaves or put into boxes. This simple yeasting process, raises the temperature and natural yeasts in the air break down the sugars to acid, when certain enzymes are activated to develop the chocolate flavoured compounds. At the same time the bitterness and astringency of the beans are also toned down.

Collecting freshy fermented cacao beans in Ambanja, Madagascar

The beans, now a rich brown colour are ready for drying either in the sun or artificially. After fermentation, the beans are still bitter and gradually acquire their characteristic chocolate flavour after drying in the sun. The best chocolates are made from sun-dried cacao beans.

Cacao beans drying in the sun on movable dryers in Ambanja, Madagascar