Fermentation: The Magical Step to Amazing Chocolate by The Chocolate Journalist

Thanks to Sharon Terenzi aka The Chocolate Journalist for letting us share this interesting article on the importance of fermenting cocoa beans. 

What does chocolate have in common with wine, bread and beer?

Certainly, they are all foods that give great pleasure. Without them on our tables, we won’t feel the same satisfaction. But what bonds these foods together is something more than taste buds stimulation. It’s a deeper connection to the Earth and its smallest inhabitants: bacteria and fungi.

In fact, a third of the foods in our diet is made edible by the action of these microbes.

Chocolate, wine, bread, beer, but also cheese, coffee and tea have to undergo a natural transformation that turn them from raw material into the products we know.

The magical step we need to thank is called FERMENTATION.

Beans from the pod

Cocoa beans are fermented to develop the typical chocolate flavour.

Michael Pollan, internationally recognized American author and food activist, dedicates an entire episode of his new TV-series COOKED (now streaming on Netflix) to fermentation.

His introduction highlights the fascinating side of this process:

“Of all the different transformations we call cooking, I think fermentation is the most miraculous, and the most mysterious. That is because it doesn’t involve any applied heat at all.

This is food and drink made strictly through the action of bacteria and fungi. They perform all the transformations that normally we need heat to make happen.

People don’t realize, as they walk through the supermarket, how many fermented foods are there”.

The foods we enjoy the most have to be fermented to develop their peculiar flavors. Chocolate makes no exception.

Chocolate makers will tell you that the most crucial step in chocolate making is fermentation. Roasting is also important, but there is just so much a skilled maker can do with poorly fermented beans.

This is the reason why many craft chocolate makers travel often to the places of origin that supply them with cocoa beans. They want to make sure that the post-harvesting processes, especially fermentation, are done properly.

How does fermentation in chocolate work then?

Beans from the pod

The real RAW state of cocoa beans inside their cocoa pods.

After the cocoa pods are carefully harvested, they are opened manually with a machete. Inside there are the cocoa beans surrounded by a white slime. Both are taken out of the pods, dumped into buckets and brought to the place dedicated to the fermentation.

In most cases, the fermentation of cacao happens in big wooden boxes. This is because high temperatures help the yeasts and micro-organisms work on the cacao. If the content of the pods was dropped on the floor and spread out flat, the fermentation process will be slowed down. In the meantime, the seeds could keep germinating, making the cocoa beans very bitter and unusable for chocolate production.

Putting the beans surrounded by the slime into big boxes helps the temperature to rise inside the box and the fermentation process starts quickly. To raise the temperature even higher, the boxes are covered with either banana leaves or jute bags.

The fermentation can now begin.

Yeasts and microorganisms start working on the pulp, creating alcohol and generating heat. The temperature rises to 40°/ 45°C (104-113°F) during the first 48 hours of fermentation. This is why something like RAW CHOCOLATE doesn’t exist.

The pulp starts to break down and drain away, leaving space for more air and bacterial activity. In the meantime, the seeds are killed and germination (that will make the beans awfully tasting) is prevented.

Fermentation will last between 3 to 7 days depending on many factors (type of beans, quantity, fermentation method, etc). When the beans have reached a “chocolate color”, they can start the drying process.

So why are chocolate makers so obsessed with fermentation again?

From the ICCO (International Cocoa Organization), we learn that:

“The death of the bean causes cell walls to break down and previously segregated substances to mix. This allows complex chemical changes to take place in the bean such as enzyme activity, oxidation and the breakdown of proteins into amino acids.

These chemical reactions cause the chocolate flavor and color to develop”.

This is why fermentation is such a crucial stage: it has a HUGE influence on how the chocolate will taste.

Greg D’Alesandre, cocoa sourcer for San Francisco based Dandelion Chocolate, travels often to exotic places around the world to find the best beans to be transformed into chocolate.

He agrees on the importance of fermentation to make great chocolate:

” Fermentation and drying are where the flavors develop.

They account for over half of the flavor of the beans (it’s hard to quantify, but I consider the 4 contributors to be terroir, genetics, fermentation, and drying.)

You can take mediocre genetics and make them taste pretty good with appropriate post-harvest processing. You can take good genetics and make them taste amazing with good post-harvest processing. You can also take the best genetics in the world and make them taste absolutely awful with bad post-harvest processing.”

Chocolate makers care a lot about the fermentation process. Nobody wants to work with poorly fermented beans. But the rules about what can be defined “well-fermented” beans are changing. It’s not about objective and standard cut tests anymore. The only guideline is the result that chocolate makers want to achieve.

Greg explains:

” The thing that has started to change in terms of understanding fermentation in relationship to high quality chocolate is that everyone is not trying to achieve the same results."

I have had chocolate experts who have been in the industry for years walk into Dandelion, taste chocolate, and say the beans are under-fermented.  The question I always follow-up with is “Does it taste good?”, which always gets odd looks. Most people who have been in the industry for a while believe that is an irrelevant question.

The belief has been that cocoa beans are either under-fermented, well fermented, or over-fermented.

Many experts believe the flavor is irrelevant. That fermentation isn’t subjective, but objective. That there is right and wrong, and under-fermented is wrong.

A lot of craft chocolate makers are looking at it differently.

They are exploring the boundaries and will make chocolate that many experts might consider “bad” but many customers really enjoy. Rather than focus on determining an absolute fermentation percentage regardless of the beans, we at Dandelion make a small batch of chocolate to taste the beans. We make chocolate as we only use beans and sugar and largely make 70% chocolate. So why not add 30% sugar and taste something closer to your final product?

The other great part about fermentation and drying is that we can change them relatively quickly. Changing your terroir is impractical. Changing the genetics of your trees takes years. Changing your post-harvest processing can happen over the course of months.

When we meet someone who wants to improve their cacao, this is clearly the place to start.”

Many rules in the fine chocolate industry are being changed by curious craft chocolate makers. Also fermentation, crucial step to achieve great chocolate, seems to be fertile terroir for innovation.

You can find more about Sharon and read her blogs via her website or email her


To read the article on Sharons' website visit here: http://thechocolatejournalist.com/fermentation-magical-step-chocolate/