With espresso shops sprouting on almost every city block across the country, coffee could win honors as the best new old drink. Only water is consumed more than coffee and tea combined. Indeed, caffeine has proven itself a potent central nervous system stimulant.
Coffee is brewed from the seeds of the coffee plant.
In the case of caffeinated sodas, trimethylxanthine is added during processing. The caffeine level in coffee and tea is as varied as the response of people who drink them. Instant coffees tend to be lower in caffeine, ranging from 40 to 110 mg per 5 ounces. Brewed teas have from 20 to 110 milligrams. In coffee, the caffeine content depends both on the type of bean and on the roasting and brewing process.