A popular choice for those who love the taste of coffee, minus the effects of caffeine whether someone is sensitive, completely decaf or would prefer an evening cup without disrupted sleep. Decaf has seen many iterations over hundreds of years, and what drives this demand is the popularity of decaf, which removes enough caffeine, and retains an acceptable flavour. Unfortunately the pervasive notion about decaf coffee is the compromise on taste. There are terrible ways, and great ways to remove caffeine from coffee without ruining the taste. Let's run through them.
ORIGIN
Friedlieb Ferdinand Runge pioneered the first decaffeination of coffee beans in 1820. Despite this, Runge did not further this endeavour, and it wasn't until 1906 that German merchant Ludwig Roselius patented the first commercially available decaf coffee process and beans. The Roselius process involves steaming roasted coffee beans in with a brine solution, and then using benzene to extract the caffeine. Unfortunately Benzene is a harmful human carcinogen so this process has long been abandoned.
THE QUEST FOR GOOD DECAF
For better quality taste, the future methods decaffeinate the coffee prior to roasting. Decaffeinating post roast can lead to greater loss of aromatics and flavour compounds. Some decaf methods are better or worse at achieving good taste, the former tends to be higher in price. In specialty coffee, we lean towards better methods which bring out delicious flavour characteristics that may be lost from a cheaper method used in commodity coffee.
CHEMICAL METHODS
Who wants chemicals near their coffee? Whilst 'chemical decaf' may trigger a sentiment of bad for your health, these methods have been tried and tested thousands of times, approved by EU and FDA food regulations as safe.
Methylene chloride
This direct method of decaffeination involves soaking green coffee seeds in water, then flushing with methylene chloride to extract caffeine, then the methylene chloride is rinsed out.
Ethyl acetate
The indirect method of decaffeination involves steeping green coffee seeds in hot water to dissolve the caffeine from the seeds into the water, the water is then separated from the coffee seeds. This flavoured water is treated with ethyl acetate to remove caffeine, then the water is added back to the seeds, absorbing flavour and aroma compounds; A great way to restore these unique flavour compounds.
SWISS WATER
The Swiss pioneered the first chemical free decaffeination process in 1933, later made as a commercially available method in 1980. Coffee seeds are soaked in hot water to dissolve caffeine, then the water is passed through an activated charcoal filter. The large size of caffeine molecules binds to the charcoal filter, allowing the rest of the flavour and aroma compounds to pass with ease. The caffeine free beans are thrown away, then caffeinated beans are added, and the decaf water is mixed with new coffee seeds. The aroma and flavour compounds can't dissolve, and only the caffeine moves from the seeds into the water.
Arguably the best method of decaffeination with the least possible loss of flavour and aroma compounds. If you want to experience exceptional decaffeinated coffee, we highly recommend a Swiss water decaf to enjoy a caffeine free experience full of the complex layers of coffee flavour.
CO₂ (carbon dioxide) DECAF
The CO₂ method was the most recent development in decaf processing, developed by Kurt Zosel of the Max Planck Institute in 1967. After using CO2 extraction on targeted compounds from various mixtures, Planck realised this method could be set on extracting solely caffeine from green coffee seeds. This chemical free processing method is a remarkably efficient and chemical free method!
Water soaked green coffee seeds are sealed inside a stainless steel extraction vessel, then liquid CO₂ is forced into the vessel at whopping 1000 pounds of pressure per square inch! This high pressure CO₂ is known as supercritical CO₂, which acts a solvent targeting and extracting caffeine and some water. Excess caffeine is separated and sold on to be added to products, and the remaining CO2 is then recycled for the next batch. The result is a decaf green coffee which roughly 96% of the caffeine removed, with a smooth full body, and less exotic fruity tasting notes. CO2 processing is not the best for specialty coffee, and tends to be used for bulk quantities of commercial grade coffee in the supermarket.
OUR FAVOURITES
Coffee: Colombia Sugarcane Decaf
Origin: Colombia Region: Huila Farm: Various Small Holders Varietals: Castillo, Caturra, Colombia, Tabi, Typica Altitude: 1200 - 2000 MASL Process: Washed, Ethyl Acetate Decaffeinated SCA Score: 84