“The mind is aroused, and ideas pour forth like the battalions of the Grande Armée.” That’s how the 19th-century French writer Honoré de Balzac described the effect of coffee on his imagination, an experience akin the eye-opening effect the drink has on so many coffee lovers.

Give credit for coffee’s arousing powers to C8H10N4O2, the alkaloid chemical compound also called as “1, 3, 7-trimethylxanthine,” more commonly known as caffeine. Also credit those arousing powers with the inspiration for developing decaffeinated coffee.

Caffeine Levels in Brewed Coffee and Espresso Coffee
Found naturally not just in coffee but also in tea and chocolate products, caffeine is added to many soft drinks and to aspirin as well. But caffeine concentration is highest in coffee. A 5-ounce cup of regular drip-brewed coffee contains on average 115 mg of caffeine, while the same amount of percolated coffee averages 80 mg and instant coffee about 65 mg. By contrast, a cup of tea of the same size has between 20 and 50 mg depending on brewing time and a cup of hot chocolate about 5 mg. A 2-ounce shot of espresso, being more concentrated than regular coffee, has approximately 100 mg of caffeine.

Regardless of its source and concentration, caffeine takes about 45 minutes to be absorbed into the bloodstream, Scientists have found that it increases brain cell activity while restricting blood vessels in the brain. In reaction to this heightened activity, the pituitary gland releases adrenaline, increasing the heartbeat rate and causing the liver to send sugar into the bloodstream. Thus, caffeine causes a heightened sense of awareness, one of the main pleasures offered by drinking coffee.

Methods for Producing Decaffeinated Coffee
Of course, some coffee drinkers want to enjoy the pleasures of coffee’s flavor and aroma without the resulting alertness, particularly when they take coffee in the evening.

That was the inspiration for decaffeinated coffee, achieved through a process pioneered in Germany back in 1820 and first launched on a commercial scale in that country in 1906. The classic decaffeination technique, still widely used today, starts by steaming green coffee beans in, which plumps them up and makes them more porous. Then the beans are mixed with the solvents methylene chloride or ethyl acetate, which remove most of the caffeine without affecting the essential oils that are the source of coffee’s flavor. A subsequent steaming removes the last traces of the chemical.

Another decaffeinated coffee method, favored by coffee lovers who don’t like the idea of their coffee being subjected to chemical solvents, is Swiss water process decaffeination, a process first developed in Switzerland in the 1930s. In simple terms, green coffee beans are soaked in very hot water, into which their caffeine is dissolved. The resulting extract is filtered through activated charcoal to remove the caffeine, and the liquid, which contains some flavor compounds, is then reabsorbed by the coffee beans before they are roasted.

Whichever process is used, the resulting coffee is on average 97 percent caffeine free, with a brewed 5-ounce cup containing on average just 3 mg of caffeine—and more than enough good coffee flavor to arouse the senses without keeping the coffee drinker awake!