By Harold McGee
Dried fermented cacao beans are less astringent and more flavorful than unfermented beans, but their flavor is still unbalanced and undeveloped, and often dominated by vinegary acetic acid. After selecting, sorting, and blending the dried beans, the chocolate manufacturer roasts them to develop their flavor. The time and temperature vary according to whether the beans are to be roasted whole, in their thin shell, or as the cracked inner kernels, the nibs, or as nibs that have been ground into small, quickly heated particles. Whole beans take 30–60 minutes at 250–320°F/ 120–160°C. This is a much gentler treatment than coffee beans require, thanks to the abundance of reactive amino acids and sugars that readily participate in Maillard browning to generate flavor. In fact, gentle roasting helps preserve some of the flavors that are intrinsic to the beans or developed during fermentation.