Did You Know That Chocolate Is Fermented?

While the chocolate production steps of roasting, milling and tempering are well known for their impact on the final product, one that can have the greatest flavor impact is often forgotten. Much like kimchi and sauerkraut, cacao beans too require fermentation in order to create the chocolate we all know and love. 

The Science Behind Fermentation

Most fermentoriums are located at or nearby the place of harvest. Because of the time sensitive nature of the process, most beans will be sent off to be placed in wooden boxes for fermentation within hours of harvest. This is true of both the Guatemalan and Belizian cacao that Tangle currently uses.

First, after the harvest of the cacao pods, the beans are removed. (We’re going to call them beans just because, even though they are actually the seeds of the cacao fruit, these wonders of nature are typically called beans.) At this stage they are coated in a delicious, spongy sweet/sour pulp and are pale, basically white in color, and must undergo a long transformative path to develop into the chocolate color we expect. 

The beans, placed in boxes and covered in banana leaves, burlap, or plastic, now begin the fermentation process. The natural sugars contained in the pulp are converted to alcohol. Next the anaerobically occurring yeast will consume that alcohol and begin producing heat within the boxes or under the blanket of leaves. As the heat rises the beans slowly begin to dry out, and the  water from the pulp is drained from the bottom.

Once the fermentation sites reach a high enough heat, the yeast will naturally die off leading to the introduction of other bacteria. The beans are stirred and turned and gradually moved through several tiers of cascading fermentation boxes as the pH changes to become more acidic and the bean transforms. The now “chocolate brown” bean contains peptide chains known as flavor precursors which will further develop through the roasting process.

Flavor of Fermentation

Fermentation is an incredibly delicate process. Too long and the flavors may turn rancid, too short and the bean will be overly basic leaving a bitter and tanic taste in one's mouth. Proper fermentation requires the natural development of a microbiome of yeast and bacteria. 

Knowledge around how to carry out the fermentation practice stems from an intimate understanding of the environment in which the beans are grown. This knowledge is often passed down through generations of small family farmers. In Guatemala, ADIOSEMAC, an organization that helps bring together indigenous farmers in the Cahabón region of Guatemala, centralizes this knowledge and the fermentation process of multiple small farms. Through organizations like ADIOSECMAC, processing capacity of fermented beans has grown over the past 10 years. And in Belize, Maya Mountain fulfills a similar role. Because of the small time window between harvest and the start of fermentation, all fermentoriums are hosted in the same regions that are viable for growing. Because no fermentation on any commercial scale takes place overseas, the process can become relatively out of sight, compared to roasting and milling.

In the production of direct bean to bar chocolate with single origin cacao harvests, we can gain a sense of how one region’s fermentation process will give nuance to the flavor of the chocolate. Just as the growing environment affects the plant, it also shifts the microbial state that the beans enter for fermentation. The specific strains of lactic acid bacterias and yeasts will differ depending on the growing region, and are affected by the temperature and the altitude of the fermentation environment.

What Fermentation Means for Us

As a single origin bean-to-bar operation, we treasure the origin of our beans and are able to maintain a closer relationship with those working on all steps of the production process. Guatemalan beans from the Cahabón region, and the new Maya Mountain beans from Belize that we are also working with, contain a unique flavor profile that tells the story of their growth, harvest and fermentation all before they are turned into chocolate here in Northampton. The way that we roast and mill the beans further develops the flavor. And the fact that we don’t use any additives that could mask any potential off flavors that might occur during fermentation means that the quality of the bean remains essential to the flavor of our product, and is something that should be tasted in the end result.