For centuries, chocolate in its various forms has been one of the world’s greatest delicacies. Even before Christopher Columbus discovered the New World in 1492, the ancient Mayan and Aztec cultures prized chocolate. It was used as an aphrodisiac, for its energizing quality as well as a form of currency. Chocolate in the form of crushed cocoa beans is derived from the seeds of the cacao tree and was originally consumed only as a beverage up until the 1800’s.
Raw cacao pod containing cocoa beans.
There are primarily three varieties of cacao grown on a commercial basis: Criollo, Forastero and Trinatario. Successful cocoa tree plantations are situated at Longitudes between 200 North of the Equator and 200 South of the Equator.
Criollo cacao trees are considered to be of the finest quality, but unfortunately produce low yields and are susceptible to damage and disease. For this reason, Criollo cacao only accounts for a very small amount of the overall world crop. Forastero cacao trees account for the majority of the world crop because it produces higher yields, but lacks the flavour complexities of the Criollo bean. The Trinatario cacao tree is a hybrid combination of the Criollo and Forastero cacao trees. As a hybrid, the end result exhibits advantageous properties of both Criollo and Forastero trees.
Not dissimilar to grape growing for the wine industry, cacao is affected by the type and quality of the soil where it is cultivated. For example, a Forastero cultivated and fermented under perfect conditions can produce a far superior bean to a Criollo grown and fermented under less desirable conditions.
Once the pods are ripe for harvesting, the cocoa beans and the pulp are extracted from the shell and fermented (takes about five days.) During the first stages of the fermentation process, the temperature of the bean rises naturally. This kills the live bean and stops the germination process.
The main function of the fermentation process is to develop the flavour precursors which permit the enhancement of chocolate flavours produced once the beans are roasted. Without the fermentation process, chocolate flavours would not exist. The fermentation process is assisted by native yeasts, enzymes and bacteria which cause the liquefaction of the pulp and allow it to run off the beans.
Once the fermentation process is complete, the beans must be dried. This stops the fermentation process and stabilizes the beans for shipping and storage. Up to this point, these processes occur at the plantation.
Cocoa beans arrive at the manufacturer from the plantation with impurities. These can include small twigs, metal, stones, etc. Cleaning is conducted at several stages and includes mechanical sieving, use of magnets to remove tramp metal, and dust extraction. At this point, some manufacturers blend other types of cocoa beans to alter the flavour profile of the finished product.
Once cleaned the beans are roasted to further enhance and develop the chocolate flavour. Beans are roasted at differing temperatures depending on the desired flavour profile. After the roasting is completed, the beans undergo a process called Micronizing. This process includes the breaking of the beans into pieces. This process can occur either before or after roasting. Once broken, the bean consists of two parts, the shell and the nib. The Micronizing process ensures that the shell is completely detached from the nib so that it can be sifted apart and separated out from the batch during the winnowing process. The winnowing process employs the use of a series of sieves combined with air flow to remove the shells.
Once the shells are successfully removed, the grinding process can occur. During this process the nibs are crushed to create chocolate liquor. At this point the chocolate liquor is either pressed to separate the cocoa butter from the cocoa powder or it is mixed into a batch of chocolate.
The mixing process combines all the ingredients to create a batch of chocolate. Chocolate liquor, sugar, vanilla, lecithin and sometimes milk solids are mixed in to create a homogeneous blend.
After mixing, the refining process is implemented to reduce the overall particle size of the mixture. The chocolate liquor typically is very coarse in texture. Reduction of the particle size is necessary so that it is not felt or detected on the palate when the chocolate is consumed. Fine chocolate has a smaller particle size than lesser quality brands. Refining is accomplished by running the chocolate batch through a series of either steel or stone rollers. This creates shear stresses that crush the particles and reduce them to the desired size.
Conching is the next process in the production of chocolate. The refined chocolate bears little resemblance to the final product chocolate. The mixture still contains volatile acids present in the fermentation process and the mixture has a sour taste to it. Conching removes the volatile acids and most of the remaining traces of water by evaporation. This is accomplished by exposing the chocolate to long term heat, oxygen and agitation. The end result is the removal of the sour taste/odor as well as improvement in the viscosity of the chocolate.
After conching is complete, the chocolate must be tempered then deposited into a mold (block, bars, callets, or some other solid form) and cooled to promote proper crystallization. The chocolate is now ready to be sold to confectioners.
An optional step in the above process is called Dutch processing. This is accomplished by treating the cacao with an alkali substance (usually potassium carbonate, K2CO3.) This can be completed at various points in the production process, including treating the whole beans, nibs, chocolate liquor, or cocoa powder. Normally it is the nibs that are treated and the purpose of Dutch Processing is to remove the acidic and sour flavours of cacao. The process also darkens the color.