Nature vs Nurture in Cocoa

There is a lot of discussion and interest on this point: what are the contributions of genetics, terroir, and post-harvest processing when it comes to the flavor of cocoa (and how chocolate gets its taste)?

Let’s conduct a thought experiment to examine the complexity of looking for answers.

Imagine that you have the ability to plant grafted seedlings from the same mother tree on 1Ha of land in two very different locations - different altitudes, different soils, different rain and wind patterns, different slopes so even the pattern of the sun is different. These differences related to place are what we think of as terroir.

We would imagine - and would expect based on our experience with other crops - that the fresh cocoa beans, and maybe event the fresh pulp, would taste different. The genetics of the tree are modified by the terroir.

However, we don’t eat fresh cocoa beans as a general rule. They are fermented. In order to test the relative contributions of genetics, terroir, and post-harvest processing we need to control for all of the variables.

Going back to the above scenario with exactly the same genetics planted in two different places.

If the post-harvest practices between the two places are different - the resulting beans will taste different. And even if the post-harvest practices are substantially the same, differences in the presence and relative dominance of yeast and bacteria strains play a part in flavor development. What’s the more important contributing factor here? Genetics? Terroir (and this includes microbiology, not just factors we can see and taste and experience physically)? Fermentation? Drying?

To find out, it is necessary to be able to control fermentation and drying precisely enough to be able to understand their influences. And this means applying science, rigorously.

Based on my experience working with Ingemann in Nicaragua and with Zoi Paplexandratou on my project down in Mexico, it is possible to take the same genetics and terroir and generate very different flavors consistently. You can see this in the Friis-Holm double turn and triple-turn Chunos. The same variety and the same overall length of fermentation, the primary difference is that one pile gets turned twice and another gets turned three times. Ingemann has expanded on this concept and now markets Chunos (i.e., the same genetics) with six different flavor profiles. The differences are created by differences in fermentation protocols, which are in turn driven by an understanding of the microbiology and chemistry underlying what’s going on. And, our understanding of fermentation is much better developed than drying.

And this is before we event start talking about other confounding factors, one of which is the presence of other varieties of cacao within pollination range - now known to be 3km. If the varieties close to one of the two areas are different from the varieties in the other, then there is the possibility that differences in pollination could be a part of the difference in flavor. Is that genetics? Terroir? What? Another confounding factor is the introduction of tailored cultures. (BTW, everything that Ingemann is doing in production is done with naturally-present yeasts and bacteria not the introduction of cultures.)

In some places, “pre-fermentation” techniques are implemented. One such technique is resting pods between harvesting and opening. In other places, “pre-drying” techniques are implemented. One such technique is to put the beans in sacks after fermentation is complete and letting them sit in the sacks overnight. IMO this is another fermentation step, not a drying step because there is little to no moisture loss in the beans and temperatures in the center of the bag may still be elevated.

In my mind, it’s impossible to say reliably that beans of the same genetics grown in different places will have the same basic flavor profile ... unless the basic microbiology and post-harvest protocols are substantially the same. The same genetics, planted in different places, subject to different post-harvest processes should have recognizable differences in flavors (that will result in chocolate with different flavors even when processed substantially the same way).

I am working on a project proposal for #CacaoMEX in Central America right now (ahoritita!) and one sub-project is to run an in-situ test with the same variety (grafted monoculture) in different locations to increase our understanding of the nature/nurture question as it applies to cocoa.

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lbrindley
lbrindley

Very interesting article about the genetic differences between cocoa beans. How does the drying and fermentation process change based on the desired flavor of chocolate (i.e. white, milk or dark chocolate)?

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