CCN-51: What Do We Ask a Cacao Tree to Be?

In the craft chocolate world, we sometimes talk about cacao as though there are good varieties and bad ones.

Old varieties are precious. Fine-flavour cacao should be protected. Modern high-yielding varieties tend to make us a little more suspicious.

And then there is CCN-51.

Few cacao varieties have such a complicated reputation. Chocolate makers often dismiss its flavour, and there are real concerns about what happens when it replaces more diverse cacao populations. And yet farmers keep planting it.

In the July 2026 issue of the Journal of Agriculture and Food Research, researchers looked back at nearly two decades of scientific work on CCN-51. What interested me wasn't really whether they thought CCN-51 was good or bad. It was how much the questions have changed. Early research was very much about productivity. More recently, people have been looking at flavour, fermentation, food safety and quality.

And perhaps that's a better way to think about CCN-51.

Not whether it's a good cacao or a bad cacao, but what we actually expect a cacao tree to do.

A Tree Created to Solve a Problem

CCN-51 was developed in Ecuador by cacao breeder Homero Castro Zurita, who spent years crossing and selecting cacao, looking for trees that could perform better under difficult growing conditions.

What he ended up with was a remarkably capable tree.

CCN-51 is productive, adaptable and self-compatible. It has resistance or tolerance to several important cacao diseases. Its flowers pollinate successfully at relatively high rates and its pollen remains viable considerably longer than that of many Nacional cacao types.

These aren't really the things we talk about when we're tasting chocolate.

But if you grow cacao, they're pretty important.

If disease keeps destroying your crop, or your trees simply aren't producing enough cacao for the farm to work, a tree that produces reliably starts to look very different.

CCN-51 spread through Ecuador and then into other cacao-growing countries in Latin America because it solved some very real problems.

The View from the Farm

We love extraordinary chocolate.

We want floral aromas, fruit, spice, acidity and all the strange complexity that cacao can contain.

But a farmer also needs a cacao tree that produces cacao.

In trials in Ecuador, CCN-51 produced substantially more than the Nacional-type clones it was compared with. The scientific literature reports typical yields of around 1,300–1,800 kilograms of dry cacao per hectare, with considerably higher production possible under intensive management.

Those numbers can sound a bit dry until cacao is how you make your living.

If one tree gives you beautiful, complex cacao but produces less and is more vulnerable to disease, while another gives you a much more dependable harvest, the choice isn't quite as simple as it looks from the chocolate-maker's side of the table.

CCN-51 didn't spread because farmers didn't care about good cacao.

It spread because they also have to make a living.

And Then There's Flavour

This is where it gets complicated.

Ecuador is famous for Nacional cacao and the extraordinary floral and aromatic qualities associated with some of it. CCN-51 generally doesn't have the same sensory profile.

Genetic, chemical and sensory research has found clear differences between them, and CCN-51 has traditionally been treated as bulk rather than fine-flavour cacao.

And as more and more CCN-51 was planted, another worry appeared. Researchers have raised concerns about other cultivars being displaced and about declining genetic diversity on farms, particularly in production systems increasingly built around CCN-51.

I think those are real concerns.

But I also think we sometimes put rather too much responsibility for flavour on the tree.

The Tree Is Only the Beginning

One of the things we talk about constantly at Cacao Huasi is that the flavour of chocolate doesn't come from genetics alone.

Chocolate is the record of everything that happened to cacao along the way.

The tree matters. So do soil, rainfall, shade, stress and ripeness.

And then the pod is harvested and the cacao is fermented.

This changes an enormous amount.

Different fermentations can lead to very different chemical and sensory development, even in cacao from the same genetics. Research with CCN-51 has shown just how much its sensory expression can change through fermentation and post-harvest processing.

There is a problem here, though.

The carefully controlled fermentation researchers can do isn't necessarily available to the person who grew the cacao. Fermentation may happen somewhere else. Beans from different farms may be combined. A farmer may have limited control over temperature or microbial populations, or simply not have the infrastructure, time or money to manage fermentation that precisely.

So when we say CCN-51 doesn't taste very good, I wonder how much of what we're tasting belongs to the tree and how much belongs to everything that happened afterwards.

Of course genetics matter. Good fermentation doesn't magically turn CCN-51 into Nacional, and nor should it.

I'm just curious about what CCN-51 can be when we give it the same attention we give to cacao we've already decided is special.

When Success Becomes a Risk

There is another problem, and strangely it comes from how successful CCN-51 has been.

What happens when one answer works so well that we start losing the others?

We sometimes talk about cacao diversity as though we're mainly trying to save interesting flavours. But diversity is much bigger than flavour.

It's like a library.

One tree may cope unusually well with drought. Another may resist a particular disease. One flowers differently, another does better in shade. Some have extraordinary flavours. Others may be carrying something that doesn't seem terribly useful to us now but turns out to matter enormously in thirty or fifty years.

We simply don't know what cacao is going to need.

So you can have a landscape that is extremely productive and, at the same time, be quietly reducing the number of options we have for the future.

That's why the newly discovered varieties in Peru could prove so important.

That's not really an argument against CCN-51. We could make the same mistake with any successful clone.

It's an argument against having only one answer.

What Should We Breed For?

This is where CCN-51 gets particularly interesting for me.

Because the lesson certainly isn't that we shouldn't breed cacao.

We absolutely should.

Disease is real. Climate change is real. And farmers need trees that produce enough cacao to make it worthwhile growing them.

There's not much use in creating the most extraordinary chocolate in the world if the farmer can't make a living from the tree that produces it.

So what do we want from the next tree?

We want yield. Disease resistance. Drought tolerance. Farmer income. Flavour. Diversity. Resilience.

Probably quite a lot more that we haven't thought of yet.

And maybe that's the point. We should be asking more of cacao breeding, not less.

What Comes After CCN-51?

In 2023, Ecuador's National Institute for Agricultural Research, INIAP, released a new cacao called EET-802, after more than twenty years of research.

In INIAP's trials, EET-802 averaged more than 2,700 kilograms of cacao per hectare, outperforming CCN-51 under the conditions tested.

But they weren't only looking at how much cacao the tree produced.

INIAP's quality and sensory evaluation placed EET-802 within Ecuador's fine and flavour cacao categories, with fruit, cacao, nuts and caramel among its reported characteristics, along with floral and red-fruit aromas.

This is the bit I find exciting.

Because the answer to CCN-51 doesn't have to be deciding that modern productive cacao is bad and trying to go backwards.

We can make the next tree better.

Can we have cacao that's productive and resilient and still interesting?

Surely that's what we should be trying to do.

A Conversation That Is Still Changing

The new 2026 analysis looked at 94 peer-reviewed studies of CCN-51 published between 2008 and 2025.

Early research was strongly shaped by questions of agronomic performance and production. Over time, the questions broadened. Fermentation, bean chemistry, sensory quality and, increasingly, food safety and contaminants such as cadmium became part of the picture.

I like that.

We're no longer only asking how much cacao this tree can produce.

We're asking what kind of cacao it produces. What happens to it after harvest. What we can do with it. What problems come with it. And what place it should have in the future of chocolate.

Those are much more interesting questions.

So, Is CCN-51 Good Cacao?

I'm not sure I care very much about answering that anymore.

CCN-51 solved problems. It gave many farmers a productive and dependable tree.

It also brought other problems and questions with it, particularly around flavour, diversity and what happens when we depend too heavily on one very successful clone.

Both are true.

Yield matters. Farmer income matters. Disease resistance matters. Flavour matters. Genetic diversity matters. What happens to cacao in a changing climate matters.

I don't think we get very far by choosing which one matters most.

We need to get better at holding more of them together.

CCN-51 didn't answer the question of what a cacao tree should be.

But it may have helped us ask a better question.

What else could a cacao tree be?

Further Reading

• CCN-51 Cocoa Research (2008–2025): Output, thematic evolution and emerging trends, Journal of Agriculture and Food Research, 2026.

• Cacao CCN-51: A comprehensive review, PeerJ, 2022.

• INIAP, EET-802 release and technical information, Ecuador, 2023.