Weekly Wake-up
Alot of science in this one!
Decaf with gas
So, as mention in the previous post, this last section of the decaf saga is about CO2 decaffeination. This method is not one I knew a ton about before but believe me, its way cooler than you’d expect.
The Science
Right! Starting off, what is supercritical CO2?
All elements have a standard temperature and pressure point, but they also have a critical point which when pushed beyond this the element becomes a supercritical fluid, this is like a half way point between gas and liquid where the element has the qualities of a gas and fills the space, but also has the density of a liquid.
In this halfway state the CO2 bonds with selective compounds very easily and thus is used in many different areas of chemistry.
The method
Firstly, the beans are steamed to bring the caffeine to the surface for easier extraction.
Next the CO2 is turned into it’s supercritical fluid form and is washed over the beans while kept under pressure so the CO2 doesn’t evaporate, in this interaction the CO2 bonds with the caffeine and is then filtered away from the now caffeine free beans. Once separated the CO2 fluid is allowed to return to its gas form, in this state the caffeine is extracted to be used in pharmaceuticals and the C02 is then able to be reused for the same method again!
Pros & Cons
This method is overall seen as a very good option to make decaf, this is mainly due to it only removing the caffeine so the flavour compounds are near completely untouched. Also CO2 is naturally occurring so it isn’t seen in the same light as the chemical options mentioned last week.
The only negative to mention is that the means to produce decaf in this way are expensive, this whole process requires quite expensive machinery but seems worth it for the minimal affect on taste.
Conclusion
Although to date I’ve not seen this method advertised on any packaging, I can say I’ll definilty give it a try when I do and if any of you have tried this style of decaf already then please comment on our Instagram as I’d love to hear any experiences with it.
Thanks for reading! Hope you all have a great week and some even better coffees.
