by Libbey Lincoln, Staff Writer
Besides being delicious, what do these foods have in common? Fermentation.
Cacao seeds consist mainly of the embryo’s leaves, two distinct cells, and water. About 80 percent of the cells store protein and fat (cocoa butter) to feed the young tree as it germinates. The remaining 20 percent contains bitter compounds to deter organisms from eating the seed before it can germinate.
Fermentation is the first important step in the development of chocolate flavor. When it occurs, it takes place where the cacao is grown. After harvesting, the cacao pods are broken open. Local yeast and bacteria begin growing on the sugary pulp surrounding the seeds and the pulp undergoes fermentation.
The acid produced during fermentation creates holes in the cacao seed cells allowing contents to mix. As a result, the bitter compounds are broken down into more complex, aromatic, and flavorful chemicals. Proper fermentation converts bland, bitter seeds into something much more flavorful, ready for drying and shipping to chocolate manufacturers around the globe.
Although dried beans are less astringent than unfermented beans, they are still quite acidic, often tasting like vinegar. Gently roasting the beans further enhances flavor.
Following roasting, seeds are broken open and the nibs are separated from the shells. Nibs are then ground which serves two purposes: releasing the cocoa butter and breaking the nibs into pieces too small to be detected by your tongue.
At this point in the process, the cocoa butter surrounding the nibs exists as chocolate liquor. The manufacturer may press the liquor to remove the cocoa butter and make cocoa powder or harden and package pure cocoa liquor for baked goods. Both products remain quite acidic.
Thankfully, many manufacturers further process, or conch, the liquor by adding sugar, milk powder and other flavors. Conching rubs the mixture of cocoa liquor, sugar, and milk solids against a solid surface which breaks the solids into smaller pieces and coats them with cocoa butter. This continues to improve the flavor through aeration and evaporation of undesirable acids. Additional cocoa butter is added to provide sufficient lubrication for the added sugar particles. Finally, the chocolate is carefully cooled to ensure stable cocoa butter crystals and a glossy, snappy, delicious product that melts perfectly on your tongue.