A chemist explains the chemistry behind decaf coffee
Decaffeination processes remove caffeine from coffee using methods like carbon dioxide, Swiss water, and solvent-based techniques, achieving 94% to 98% caffeine removal while attempting to preserve flavor and aroma.
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Decaffeination processes aim to remove caffeine from coffee while preserving its flavor and aroma. There are three primary methods used: the carbon dioxide method, the Swiss water process, and solvent-based methods. The carbon dioxide method, developed in the 1970s, utilizes high-pressure CO₂ to extract caffeine from moistened coffee beans, removing 96% to 98% of caffeine while leaving minimal CO₂ residue. The Swiss water process, introduced in the 1980s, involves soaking green coffee beans in hot water to extract caffeine and flavor compounds, then filtering the water to remove caffeine before reintroducing it to new beans, achieving a caffeine removal rate of 94% to 96%. Solvent-based methods, dating back to the early 1900s, use organic solvents like ethyl acetate and methylene chloride to extract caffeine. These methods can remove about 96% to 97% of caffeine. While ethyl acetate is considered safe, methylene chloride has strict consumption limits, and any residual amounts in coffee are well below safety thresholds. All decaffeination methods inevitably remove some flavor compounds, but techniques like the Swiss water process attempt to reintroduce some of these lost flavors. Ultimately, these processes allow consumers to enjoy coffee without caffeine, although some flavor loss is unavoidable.
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A chemist explains the chemistry behind decaf coffee
Decaffeination of coffee uses methods like carbon dioxide, Swiss water, and solvent-based techniques to remove caffeine while preserving flavor, typically leaving about 7 milligrams of caffeine in an 8-ounce cup.
- There are doubts about the quality of beans used in decaf coffee, with some suggesting lower quality may affect taste.
- Concerns about the safety of solvents used in decaffeination processes, particularly ethyl acetate and dichloromethane, are raised.
- Some commenters express a desire for better-tasting decaf options and question why genetic modifications for caffeine-free beans aren't more common.
- Experiences with different decaffeination methods vary, with some preferring CO2 over Swiss Water for flavor retention.
- There is a call for more attention and priority to be given to high-quality decaf coffee in the market.
19 commentsAnd a quick follow up: https://youtu.be/IszQ2JR3Olc
https://www.youtube.com/watch?v=RIbff5iD0GQ
and from coffee here:
(My initial though was, "then how do you get the cafeeine-free coffee in the first place", but I see the answer is that you can decaffeinate liquids by running them through charcoal filters... something you can't do with solid beans.)
Personally, I've found the CO2 method to have a lot more flavor than the Swiss Water. I also found the CO2 beans don't deteriorate as quickly as the Swiss Water beans.
I've tried, conservatively, a dozen and a half of different decafs available here in the EU, and some a markedly better than others. In fact, most are outright garbage with an exception of two that are virtually indistinguishable from each other even though they are from unrelated brands. So I wonder if the differences are due to the process rather something else.
I drink regular coffee.
There's a growing anti-drug sentiment that should be a great tailwind.
It's hard for me to find as good tasting a bean as it is with non-decaf. I've tried subscription services or pay huge shipping and product premium from some boutique retailer, the beans are always just ok. Decaf still doesn't get enough priority as the product itself, always an afterthought it feels like.
Another common solvent not mentioned here is Dichloromethane. It's a pretty clear cancer causing agent https://www.reddit.com/r/todayilearned/comments/pr8k9v/til_s...
You know what else is a solvent for decaffeinating coffee? Benzene. https://en.wikipedia.org/wiki/Benzene#Health_effects
Don't drink decaf. The CO2 method is pretty safe but the simple fact is unless you're sure how your beans were decaffinated you're better off not drinking it.
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A chemist explains the chemistry behind decaf coffee
Decaffeination of coffee uses methods like carbon dioxide, Swiss water, and solvent-based techniques to remove caffeine while preserving flavor, typically leaving about 7 milligrams of caffeine in an 8-ounce cup.