Several types of chocolate can be distinguished. Pure, unsweetened chocolate contains primarily cocoa solids and cocoa butter in varying proportions. Much of the chocolate consumed today is in the form of
sweet chocolate, combining chocolate with
sugar.
Milk chocolate is sweet chocolate that additionally contains milk powder or condensed milk. "
White chocolate" contains cocoa butter, sugar, and milk but no cocoa solids. Chocolate contains
alkaloids such as
theobromine and
phenethylamine, which have some physiological effects in humans, but the presence of theobromine renders it toxic to some animals, such as
dogs and
cats. It has been linked to
serotonin levels in the brain.
Dark chocolate has recently been promoted for its health benefits, as it seems to possess substantial amount of
antioxidants that reduce the formation of
free radicals.
Alongside
milk chocolate,
white chocolate and
dark chocolate are also common chocolate varieties.
White chocolate is formed from a mixture of
sugar,
cocoa butter, and
milk solids. Although its texture is similar to milk and dark chocolate, it does not contain any cocoa solids. Because of this, many countries do not consider white chocolate as chocolate at all. Although first introduced by
Hebert Candies in 1955,
Mars, Incorporated was the first to produce white chocolate within the
United States. Because it does not contain any cocoa solids, white chocolate does not contain any
theobromine, meaning it can be consumed by animals.
Dark chocolate is produced by adding fat and sugar to the cacao mixture. The
U.S. Government calls this "sweet chocolate", and requires a 15% concentration of chocolate liquor. European rules specify a minimum of 35% cocoa solids. Dark chocolate, with its high cocoa content, is a rich source of the
flavonoids epicatechin and
gallic acid, which are thought to possess cardioprotective properties. Dark chocolate has also been said to reduce
the possibility of a heart attack when consumed regularly in small amounts. Semisweet chocolate is a dark chocolate with a low sugar content. Bittersweet chocolate is chocolate liquor to which some sugar (typically a third), more cocoa butter, vanilla and sometimes
lecithin have been added. It has less sugar and more liquor than semisweet chocolate, but the two are interchangeable in baking.
Unsweetened chocolate is pure
chocolate liquor, also known as bitter or baking chocolate. It is unadulterated chocolate: the pure, ground, roasted chocolate beans impart a strong, deep chocolate flavor.