Chocolate products are available in great variety.
Cocoa powder is either alkalized or nonalkalized. Alkalized cocoa powder contains potassium carbonate, sodium carbonate, sodium hydroxide, or magnesium, all of which neutralize the naturally occurring acids and make the powder easier to dissolve in liquids. Cocoa powder may also contain added starch (e.g., corn starch) to keep it from caking during storage. Unsweetened cocoa powder is used primarily in baking. Sweetened cocoa powder is often mixed with hot milk or water to produce "hot chocolate" or "hot cocoa."
Unsweetened chocolate contains up to 75 percent cocoa solids, and no added sugar or milk products. It is used primarily for baking, because although it has a chocolate flavor, it is too bitter to eat on its own.
Dark chocolate is also known as "bittersweet" or "semisweet" chocolate. It contains a high percentage (up to 75%) of cocoa solids, and little (or no) added sugar. Semisweet chocolate has a rich, intense flavor, and is found in candies and the chocolate morsels (chips) used in baking.
Milk chocolate contains powdered or condensed milk; it is a sweet, mild-flavored type of chocolate. It contains approximately 20 percent cocoa solids. Many candy bars are made with milk chocolate.
Both semisweet and unsweetened baking chocolates are available. Baking chocolate is sold in one-ounce (28-gram) squares, which are convenient for use in recipes.
Couverture is a high-quality chocolate used in making specialty candies and truffles. It contains a high percentage of cocoa solids, which gives it a high gloss.
White chocolate is not really chocolate, since it is not made from cocoa beans. However, it is made from cocoa butter to which milk, sugar, and vanilla extract have been added, and it is similar to chocolate in texture. White chocolate is very sweet.