Methods of Decaffeination in Coffee
So many of us know the effects that caffeine has on our body and how it acts as a stimulant. This can have a negative effect on our body. Too much caffeine in our system can increase blood pressure and effects the bodies nervous system which can be a trigger of anxiety.
Therefore, we have decaf coffee to take away the affect that drinking coffee has on our body. How do they do this you may ask? They use many different methods of decaffeination and I am going to explain these to you, as well as explain the positives and negatives of each one. Decaf coffee is great for those occasions where we want to enjoy a delicious cup of our favourite drink on a night without it keeping us up all night because of the effects of the caffeine it contains.
First method of decaffeination dates to 1905 created by Ludwig Roselius this involves the steaming of the coffee beans with brine solution. Then using a chemical compound called “benzene” which would extract the caffeine. This method of decaffeination is no longer used as “benzene” can cause cancer in living tissue which we obviously do not want.
The Swiss Water prosses
Developed in the in the 1970’s due to the negative impact that the original method had on consumers health, this prosses involves soaking the beans in hot water for a couple of hours to dissolve the caffeine. The caffeine solution is then passed through a charcoal filter, this is because one of the features of charcoal is that it extracts or absorbs toxins and impurities from solutions due to the carbon found within it. However, this filter can only catch large caffeine molecules an allows the smaller ones to pass through. Using this method, the coffee often loses some valuable taste, when sold is always labelled "SWISS WATER Decaf" and this method is almost exclusive to organic coffee.
The Carbon dioxide Method
This is the most recently developed method, as the name implies, uses carbon dioxide to decaffeinate the coffee, making it so we can make decaf naturally without using any chemicals which is better for our environment, while unlike the swiss water prosses, this coffee’s taste is not affected. The start of this process involves soaking the coffee beans in highly compressed carbon dioxide which extracts the caffeine. The caffeine is then removed from the carbon dioxide and passed through activated carbon filters which extracts the caffeine from the coffee again.
These two processes are both non solvent based processes. There is, however, things such as direct solvent processes and indirect solvent processes. This is when caffeine is removed from the coffee bean with help of a chemical solvent, such as methylene chloride or ethyl acetate. A direct solvent process is when the caffeine is removed from the coffee bean by directly soaking the coffee beans in the chemical solvent, whereas within indirect method the solvent never actually touches the bean because the caffeine laden water is transferred into a separate tank and is treated with a solvent.
Although in early methods of decaffeination solvents were used such as benzene these solvents have been found to have no health risks and are therefore are safe to use in this process.
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