A major impact compound, as well as the pleasant aroma and flavor components in roast coffee, is caffeine; it is the physiologically most active substance in coffee.
Coffee beans contain between 0.8 and 2.8% caffeine, depending on species and origin, and it contributes to 10 to 30% of the often desired bitterness of the coffee beverage.
Because of the adverse publicly surrounding caffeine use, many people are drinking decaffeinated coffee, in which the caffeine has been displaced from the coffee bean using hot water solution.
The latest decaffeination technology involves the use of supercritical fluid extraction with carbon dioxide.
The US and Food and Drug Administration requires that coffee must have 97 percent of the caffeine removed from the untreated green coffee beans to qualify as ‘decaffeinated’.
In EU countries, decaffeinated coffee means a maximum caffeine concentration of 0.1% related to the dry mass.
Traditionally, robusta beans are chosen for decaffeinated because they yield a higher caffeine-by-product, which is sold for medicinal and soft drink purpose.
More and more arabica coffee beans are being decaffeinated, for their superior finished coffee flavor, aroma and body, and certainly for the greatest benefit, a lower caffeine coffee product.
In order to minimize flavor and more losses, the commercial decaffeination of coffee is at present carried out on the green coffee beans, before roasting.
Decaffeinated coffee
