Cocoa beans of varied botanical origins and characteristics are farmed in a variety of tropical locations. Chocolate manufacturers use their learned expertise to formulate blends of various bean types to create unique flavor profiles. While the flavor of milk chocolate is subtle and differences are relatively easy to detect, the impact of bean selection and blending is probably more obvious in dark chocolate. This is due to its higher cocoa-solids content and the lack of interference, or muting, of the profile that the milk and caramelized characters tend to bring about.
Nib alkalization
Alkalization is typically thought of as an important phase in the manufacture of cocoa powders. The process neutralizes or alkalizes the natural cocoa product, and thereby modifies its color and flavor characteristics.
As the pH of the mass is driven upward, the color darkens and the flavor loses its acid character, taking on a deeper, more fudgelike property. Alkalization is critical to the powder manufacture as it extends the color range from the simple yellow-brown of the natural powder to a broad range of red-brown colors. It can be used to create black powder when carried to the extreme.
Alkalization can be completed at several stages of the manufacturing process, including nib treatment, liquor treatment and press cake treatment. Nib and liquor alkalization are used in preparing liquor for chocolate manufacture. Nib alkalization is thought to produce the highest-quality products. Solutions of one or more of several approved alkalizing agents (potassium carbonate being the most common) are mixed with the nibs and absorbed by the bean tissue. The nibs are then dried or roasted to complete the reaction, and are subsequently ground into liquor. Liquor alkalization is accomplished by adding the solutions of alkali to liquor ground from roasted beans or nibs.
Roasting for flavor
The roasting phase of chocolate manufacturing is considered the most critical in terms of the development of desired flavor profiles, as it is at this point where chocolate flavor, as we define it, is created from hundreds of chemical flavor precursors found within the bean.
Roasting systems are either whole-bean roasts (roasting preceding shelling) or nib roasts (shelling preceding roasting). As with other roasting processes, the desired properties are a result of a time-temperature relationship. While there are relatively unlimited parameters available to the cocoa-bean roaster, we tend to think of degrees of roast in three general categories: low, medium and high roasts. The time and temperature parameters within each of these categories are quite variable. Low roasts tend to maintain the volatility of the flavor profile. This produces more-acidic and aromatic liquors, depending on the type of beans roasted and the roasting conditions. Medium roasts, on the other hand, produce less-acid and more-balanced notes.
