“Caffeine is the most widely used drug in the world” these are the words of the writer Michael Pollan in his book entirely dedicated to you and coffee. Caffeine is a psychoactive and stimulant substance which has had a huge impact on our societies to the point of shaping our lifestyle habits: how we work, how we eat, how we interact and certainly how we sleep or rest. This substance is naturally contained in various types of seeds and plants. Plants use it as an anti-parasitic: it is produced to keep insects away, while humans use it as an energizer. By giving a very strong energy boost, humans have always tried not to take excessively high quantities and to limit it to certain hours of the day so as not to create sleep disorders. With the aim of evading these problems, the first decaffeinated coffee was put on the market in 1905.
The history of caffeine-free coffee has much older origins that date back to 1819 when the famous writer Johann Wolfgang Von Goethe gave the chemist Friedlieb Ferdinand Runge a handful of coffee beans asking him to investigate why they prevented him from sleeping. Runge dedicated an entire year of studies to this research and in 1820 he was the first scientist to identify and isolate caffeine. Runge patented a technique to decaffeinate coffee by immersing the beans in benzene, a valid procedure but harmful to health.
The first decaffeinated coffee was marketed in 1905, when German merchant Ludwig Roselius began studying the harmful effects of caffeine on the human body and then developed a method to remove this substance from coffee beans. The intuition that led Roselius to create his decaffeinated coffee was based on an accident: during a business trip to Germany, the load of coffee he was transporting got soaked in sea water. The merchant realized that the caffeine had partially disappeared from those beans without the salt water having damaged the coffee or altered its flavors. Thanks to this event, Roselius created his method, which involved steaming the beans and then using benzene to eliminate further caffeine residues.
Roselius patented his decaffeination process and founded the company Kaffe HAG to market it. The novelty was a great success initially among the German aristocracy and then throughout the world. A boost to the success of the drink certainly came during the Third Reich as Hitler and his followers saw caffeine as a poison for humanity.
Currently there are several methods for decaffeinating coffee, here we will explain the main ones:
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Water-based method or Swiss Water Process:
This process was invented in the 1980s and is still used today.
The process relies on the solubility of caffeine in water and on osmosis. Thanks to this, only some substances are able to pass through the filter. The process begins with the immersion of green coffee beans in hot water to dissolve the caffeine. The problem is that in addition to caffeine, other substances present in the coffee are also dissolved, such as sugars and other chemical components essential to create flavor and aroma. To overcome this problem, the water in which the green coffee has been immersed is passed through a carbon filter. Since the caffeine molecule is large, it remains trapped in the filter, unlike sugars, oils and other chemical elements that serve to give flavor and aroma to the coffee that are able to pass perfectly, creating a liquid that is called green coffee extract. The water infused with the green coffee extract is then used to macerate the next batch of green coffee beans. Since the green coffee extract already contains other aromatic elements, these substances are not dissolved by the beans and only the caffeine is removed.
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Decaffeinated coffee with sugar cane
This natural method is still not very widespread despite being able to best preserve the original flavors of coffee. This process is also called EA decaffeination. EA or ethyl acetate, is the essential substance for the process to work. This is a solvent generated from sugar cane and if used correctly it works to remove caffeine.
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Carbon dioxide decaffeination
In this method, green coffee beans are immersed in a highly pressurized environment of carbon dioxide at a pressure ranging from 73 to 300 atmospheres for a period of about ten hours. The pressure is then reduced and the CO2 is evaporated or passed through water.
This method removes 95 to 99 percent of the caffeine. The extracted caffeine is stored and sold to beverage and food supplement companies.
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Dichloromethane method
This method was one of the first to be used on a large scale.
Raw coffee is immersed in dichloromethane and then removed by steam. Dichloromethane is a solvent that can perfectly select caffeine and evaporate even at low temperatures.
In recent years, coffee consumption has increased significantly and a positive trend is expected for the coming years. Currently, 12% of all coffee is decaffeinated.
It is likely that in the next few years new techniques for decaffeination will be discovered and existing techniques will be improved, focusing more and more on natural methods to the detriment of chemical ones. If once decaffeinated coffees were harmful and lacking in body and flavor, today, with new techniques, we have excellent products. Recently, experiments have begun to produce coffee naturally without caffeine, the results are good but for now, given the high costs, it remains a niche product.
We must remember, however, that eliminating caffeine is not always so easy. Even if these innovative methods are effective and precise, they still extinguish some beneficial substances found in coffee. So it is not necessary to completely abandon classic coffee to switch to decaffeinated coffee; decaffeinated coffee does not mean healthier, but simply decaffeinated.
At the same time, however, eliminating caffeine is not as easy as it may seem. Although these natural methods are gentler than the previous chemical ones, they still lose some of the beneficial substances found in coffee. Therefore, it is not necessary to switch en masse to decaffeinated coffee. In fact, decaffeinated coffee does not mean healthier, but simply decaffeinated. So, unless you are pregnant, breastfeeding, or have other health problems or caffeine tolerance, feel free to consume decaffeinated coffee, but in reasonable quantities.