Theobromine (thee-oh-BROH-meen) is a white crystalline
solid that occurs naturally in cocoa beans, from which chocolate
is obtained, and, in smaller amounts, in tea and cola nuts. Theobromine
is structurally very similar to caffeine, which differs
only in the presence of a methyl group (-CH3) on one of the
nitrogen atoms in the theobromine molecule. Both theobromine
and caffeine belong to a family of organic compounds known as
themethylxanthines. Theobromine’s effects on the human body
are similar to those of caffeine, but about ten times weaker. In
addition, caffeine is metabolized more quickly, is addictive, and
increases alertness and emotional stress. It may also have serious
effects on the central nervous system and the kidneys. By
contrast, theobromine produces feelings of well-being, is not
addictive, has no effect on the central nervous system, and
provides only gentle stimulation to the kidneys. Its effects on
the body are much longer-lasting than are those of caffeine.
The amount of theobromine in cocoa beans varies widely,
ranging from 10 to 40 milligrams of theobromine per gram
of cocoa. The variation depends on a number of facts, including
the type of bean, the location where it was grown, and
the method of processing the bean. All chocolate products
contain theobromine, but the amount varies depending on
the type of chocolate. Dark chocolate contains significantly
more of the compound than milk chocolate, and high quality
chocolate tends to contain more theobromine than low quality
chocolate. The characteristic bitter taste of dark chocolate
is due to the theobromine present in it.
Theobromine is usually obtained from the hulls of cocoa
beans left over after the production of chocolate. The hulls
are crushed and then treated with an absorbent, such as
water or liquid carbon dioxide, which dissolves the theobromine.
The water or carbon dioxide is then allowed to evaporate,
permitting the crystallization of the pure compound.
