Cocoa Roasting

Like many people, I've long thought of cocoa and coffee as being fairly similar; both are complex flavor-wise, both are grown in the tropics (one at low elevation, the other high) and both are seeds that need roasting before consumption.  But  I didn't know much about chocolate production until I met Robbie Stout of Ritual Chocolate in Denver, CO who gave me a tour of his facility and explained a bit about the cocoa roasting process and making chocolate. 

 

Of course there is a large scale approach to chocolate production which is the polar opposite of truly high grade chocolate. As with large scale coffee roasting, this production has more to do with volume and speed. Low quality cocoa is roasted fast and a lot of caramelization and browning takes place. These heavy roasts cover up the inferior flavor from the lower quality cocoa.

 

Better chocolate production starts with higher quality cocoa, and the roasting develops flavors imparted through terroir, varietal, and processing. Roasts can range from 45 minutes to several hours without any sugar browning, or at least very little. The particulars of roasting can be proprietary and closely guarded, and are very much determined by the cocoa itself; the fermentation, varietal, drying, convection or conduction roasting, and so on.

 

Long roasts have several benefits: a longer roast creates elasticity in the cellular walls of the cocoa  allowing moisture and oils to escape; acidity (which can impart off flavors) breaks down; and the protective shell, or husk, of the bean loosens. The last benefit is important as it facilitates winnowing, the process of separating the nib from the rest of the material of the cocoa seed.

 

With coffee, after you roast and let the beans rest, all you then have to do is grind and brew to enjoy the final product. WIth chocolate, you have to roast and winnow (which is actually fairly similar to the dry milling which takes place after coffee has been pulped and dried, but that happens before roasting). After winnowing there are many more steps before you are anywhere near what we know of as chocolate.

 

Next step the ground nibs are mixed with sugar. Some small shops like Ritual Chocolate restrict the ingredients to only cocoa and sugar in order to more clearly express the true flavors of the cocoa, but 99% of the chocolate produced in the world is made with the addition of cocoa butter, soy lecithin, and vanilla. After mixing, the chocolate is then refined (i.e. ground) to a particle size of around 15-25 microns in order to give it a soft and silky texture.

 

The chocolate is then conched for around 3 straight days, sometimes more, sometimes less. A conche is a heated tub of sorts that slaps and churns the liquid chocolate around. The conching further breaks down the unwanted acids through prolonged heat exposure and agitation. 

 

So, if you don't want the flavors imparted by these acids in the chocolate, what flavors are you looking for? This has a lot to do with processing and terroir. Cocoa from the Chuao region in Venezuela is some of the most renowned for its delicate nutty flavor. Some cocoas from Ecuador have floral and bergamot notes like those found in washed coffees from Ethiopia. Costa Rican cocoa can be earthy and fruity with tannins, while Peruvian cocoa has a balance of fruity and nutty flavors, or  woody notes. 

 

Producing chocolate can be quite the challenge. There are less than 30 small chocolatiers like Ritual Chocolate in the US, and finding raw cocoa to work with can be difficult. There are only a few importers moving high quality cocoa into the US and a lot of the trade becomes farm direct. According to Robbie, the importers themselves generally only have 5-10 varieties of cocoa available at any time, significantly less that what can be had from green coffee vendors. Freshness is not as big a factor in raw cocoa. Unlike coffee, cocoa producers generally try to get the moisture content down to 6-7% before bagging and shipping, where as a SHG washed coffee for instance needs to be under 12% moisture content to ship and you wouldn't want it under 10%.

 

Chocolate production could provide some interesting challenges to home roasters. Learning how to read a cocoa as it roasts in order to know how well you've developed flavors and reduced acids can be a lot trickier than doing the same with coffee; but as with coffee, getting to know your materials and processing is a part of the adventure.

 

Thanks to Robbie Stout for the pictues and for all of his help with this article. The Ritual Chocolate website has a good deal of info on chocolate production.

 

- Chris Schooley

 

 


Cocoa

Cocoa pods at different ripeness levels

Cocoa in shells, ready to be cracked and winnowed

Winnowed cocoa nibs

Mixing

Refining

Chocolate ready to conche