Everything you need to know about chocolate
Cocoa PowderCocoa powder is made from roasted and ground cacao seeds from which much of the fat has been removed. It is naturally tart and acidic. A little cocoa adds plenty of chocolate flavor.
There are two types of cocoa: natural (nonalkalinized) and Dutch Process (alkalinized). Natural cocoa powder (also called unsweetened) is simply untreated cocoa powder; it is rarely labeled with the word natural on the package, but will simply say cocoa. Dutch Process cocoa ― so named because a Dutch man invented the process –– has been treated with an alkali to reduce its harshness and acidity. Along the way, "dutching" gives the cocoa a rich dark appetizing color, mellow toasted flavor, and coffee notes.
If a recipe simply calls for cocoa, use natural cocoa. Because Dutch Process cocoa is more alkaline, it may alter the chemistry in a recipe, reacting differently than natural cocoa with baking soda or baking powder. In recipes with no leaveners, natural and Dutch-process cocoa are interchangeable.
It's best to store cocoa away from herbs and spices and other aromatic substances, as it picks up other flavors relatively easily.