What exactly is caffeine?
Caffeine is a substance that can be found in numerous plants. As a natural plant protection against predators such as insects, caffeine is found primarily in coffee, tea, guarana, mate, kola nut and cocoa. Extracted from the plants, caffeine is a white, rather bitter-tasting crystalline powder. In the food and pharmaceutical industries, caffeine is often used in drinks and medicines to make use of the stimulating effect of caffeine. Chemically speaking, caffeine belongs to the methylxanthines.
Decaffeination process: How is espresso decaffeinated?
Industrial decaffeination was invented over 100 years ago by Ludwig Roselius. The Bremen merchant wanted to reduce the caffeine content for health reasons and at the same time retain the full flavor of the popular bean. The company he founded, Kaffee HAG, was long considered the epitome of decaffeinated coffee. Since then, the decaffeination processes have been continuously developed. The basic principle is extremely simple and essentially consists of the following three steps: moistening the coffee beans, extracting the caffeine, drying the coffee beans. Basically, all decaffeination processes always decaffeinate the green coffee. The challenge with decaffeination is to extract the caffeine from the unroasted coffee beans without losing the aromas and oils of the espresso bean.
First, the unroasted coffee bean is moistened in a water bath or with steam. This makes the cell walls more permeable. Next, a processing aid is added that dissolves and binds only the caffeine. This extraction agent is then removed again - and with it the caffeine. Depending on the process, the caffeine can be separated from the solvent and reused separately. This extraction process is repeated until the caffeine content is reduced to a maximum of 0.1 percent. This is the maximum value prescribed in the EU for decaffeinated coffee. Finally, the coffee beans are dried again and processed as usual. For a decaffeinated espresso, this means that the beans are roasted particularly dark and aromatic in around 20 minutes.
Depending on the extraction agent used, there are various methods of decaffeination. The processing aids ethyl acetate, dichloromethane, carbon dioxide (CO2) and water-based extraction are permitted. The method using CO2 is particularly popular. For a decaffeinated espresso, CO2 is placed in a so-called supercritical state. At a temperature of over 32.15 °C and a physical pressure of 76 bar, CO2 develops the density of a liquid, but is still gaseous. In this form, CO2 can very quickly and selectively dissolve the caffeine from the bean. All other ingredients are retained, and the caffeine extracted from the bean can be reused. Decaffeinated organic espresso may only have been decaffeinated using the water or CO2 method to ensure organic quality.
Espresso without caffeine - what does the term decaffeinated espresso mean?
There are numerous processes used to remove caffeine from espresso beans. By decaffeinating the espresso beans, the effect of the caffeine when drinking decaffeinated espresso is reduced to an absolute minimum. Caffeine-free drinks are often advertised, but is "caffeine-free" coffee really completely free of caffeine? In short: No. Even though many people use the term decaffeinated espresso as caffeine-free espresso, this is not entirely correct, because even decaffeinated coffee is not completely free of caffeine. According to EU food law, decaffeinated espresso must contain a residual caffeine content of 0.1% in order to be officially considered decaffeinated espresso. This means that decaffeinated coffee is not caffeine-free, but contains a very small amount of residual caffeine.