Coffee that has undergone a process to extract the caffeine from the green (raw) coffee before roasting.

In legislative terms, for a coffee to be called “decaffeinated”, the quantity of caffeine it contains must not exceed 0.1% of the weight of the dry product.
There are various decaffeination methods, using chemical solvents (dichloromethane or ethyl acetate, which however leaves reside in the cup) or using water. The latter method, in particular, avoids the use of chemical solvents and preserves the organoleptic properties of the coffee.
To remove the caffeine, the raw coffee is subject to steam baths, washed in water (saturated with the components to be preserved), filtered through a carbon bed and oven-dried.