Decaffeination

Decaffeination is the removal of caffeine from coffee beans, cocoa, tea leaves, and other caffeine-containing materials. While soft drinks which do not use caffeine as an ingredient are sometimes described as "decaffeinated", they are better termed "non-caffeinated" because decaffeinated implies that there was caffeine present at one point in time. Decaffeinated drinks contain typically 1–2% of the original caffeine content, and sometimes as much as 20%. Decaffeinated products are commonly termed decaf.

Friedlieb Ferdinand Runge performed the first isolation of pure caffeine from coffee beans in 1820. He did this after the poet Goethe requested he perform an analysis on coffee beans after seeing his work on belladonna extract. Though Runge was able to isolate the compound, he did not learn much about the chemistry of caffeine itself, nor did he seek to use the process commercially to produce decaffeinated coffee.

The first commercially successful decaffeination process was invented by German merchant Ludwig Roselius and co-workers in 1903 and patented in 1906. In 1903, Ludwig accidentally stumbled upon this method when his freight of coffee beans was soaked in sea water and lost much of its caffeine without losing much taste. This original decaffeination process involved steaming coffee beans with various acids or bases, then using benzene as a solvent to remove the caffeine. Coffee decaffeinated this way was sold as Kaffee HAG after the company name Kaffee Handels-Aktien-Gesellschaft (Coffee Trading Company) in most of Europe, as Café Sanka in France and later as Sanka brand coffee in the U.S. Café HAG and Sanka are now worldwide brands of Kraft Foods. Because of health concerns regarding benzene (which is recognised today as a carcinogen), benzene is no longer used as a solvent commercially.

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