How do you decaffeinate coffee? | Hacker News Reader

How do you decaffeinate coffee?

bbc.com

46 points0DHm2CxO7Lb356 comments

Note that decaffeinated coffee often still contains caffeine: “decaf coffee typically has 2-15 milligrams in an 8-ounce cup”, caffeinated is 80-100mg [1].

[1] https://www.fda.gov/consumers/consumer-updates/spilling-bean...

There are brands, expensive though, where the number is actually 0.

You literally have to use multistage subcritical CO2 filtering to reach that level. Standard methods are not good enough.

What are some of those brands?

> In 1985 the US’s Food and Drug Administration said the likelihood of any health risk from methylene chloride was so low “as to be essentially non-existent”.

This is somewhat poorly phrased. Methylene chloride is a neurotoxin and likely carcinogen, but it will be driven off by the roasting process. The boiling point of DCM is 40C, and roasting occurs at 200C, so any residual solvent should be long gone early in the roasting process. Nevertheless, this solvent is destructive to the ozone layer and should be phased out of industrial processes as much as possible.

This is another good write up on the swiss water method: https://levels.io/swiss-water/

TLDR: Swiss Water > paint thinner

Ehh, the whole premise there seems to be "chemicals bad," while acknowledging that the amount of solvent left in the coffee is negligible.

I'm not sure about you, but I prefer the amount of solvent in my food and drink to be "none", rather than "negligible".

I have no preference, because a negligible amount of solvent is, by definition, indistinguishable from none.

I have some unpleasant news for you, literally everything you have ever eaten has some level of adulterants in it. It's allowed: https://www.fda.gov/food/ingredients-additives-gras-packagin...

I'm reasonably sure the moose I shot 200km from a paved road and the vegetables I grow in my backyard are pretty free and clear.

There’s pollutants in literally every square inch of soil of anywhere mankind lives or lives near. Even seals eaten by Inuit in the Arctic Circle are polluted.

To be fair the seals are probably far less polluted than some cheap random chicken bought at the supermarket.

The fact that perfection is impossible to reach shouldn't make us abandon and do nothing about it.

Seals are quite high up the food chain so are one of the most polluted foods regularly eaten by humans. It's much safer eating herbivores than carnivores.

Not saying anything about not trying to find perfection. I'm only saying it's unlikely that anything you consume is free of contamination in 2020.

You would be incorrect. Your backyard soil is not free from contaminants, nor is the foot that the moose ate.

Some additional bad news about water if you don't like solvents in your food.

I know what you mean, and this is bordering on willful misunderstanding, but I'll still do this:

The most commonly used solvent is water. Ethanol is also a major one: https://www.worldofmolecules.com/solvents/

The Greeks called water “the ultimate solution”, because it could dissolve just about anything, given enough time. It is the original solvent.

Or do we need to restart that program to ban all use of the horrible dihydrogen oxide solvent that pollutes over 70% of the surface of the world? ;)

One does achieve "none", tis marketing hype and wasteful. For instance, if you eat or drink any fermented foods, you are regularly consuming organic solvents. Undistilled alcoholic beverages contain quite a few interesting organic solvents that contribute to flavor (and hangovers).

I'd wager that is impossible. There will always be some contamination. The important thing is that it's small enough to not cause any harm.

Amount of caffeine in regular coffee: ~100mg per cup.

Caffeine LD50: 150-200 mg/kg (according to Wikipedia).

Maximum allowed amount of methylene chloride in beverages, the dreadful paint thinner, according to the link above: 10 ppm, or about 2 mg per cup.

Methylene chloride LD50: 1.25 g/kg (again, according to Wikipedia).

I.e., you will literally die of caffeine poisoning long before the paint thinner gets you.

Supercritical CO2 Decaffeination > Swiss Water > Chemical stuff

Swiss water decaf is relatively easy to get. I've yet to see Supercritical CO2 decaf.

NileRed has some fun videos about decaffeinating things. Here’s one where he does Red Bull.

https://www.youtube.com/watch?v=oY8tz1paj6o

I drink both, caffeine in the morning and once past midday I move to decaf until as late as 5pm, I heavily favour much lower caffeine decaf. In my experience decaf tastes the best from either swiss or CO2 methods and from the beans. The best decaf can come pretty close to decent coffee but its also just as expensive as well. I find it works better under pressure immersion than drip, so more Aeropress or Turkish stove method than French press or V60.

> Roselius discovered the secret to decaffeination by accident

It’s amazing how many things we use have been discovered by accident

It would be cool if someone genetically engineered decaf coffee beans. In theory you just disable one gene, no?

There is such a variant and numerous attempts are under way to breed such a plant. There are many hundreds of natural coffee plant variants and some do produce almost no caffeine but also do not produce good fruit. So far there hasn't been much success on combining the properties, there is a commercial bean out of africa naturally low in caffeine but its not great or very available.

I think it will happen at some point.

Seems similar to the process of removing alcohol from beer while still keeping the taste.

I don't drink but I was always under the impression that alcohol-free beer doesn't quite taste the same (i.e. that the process of removing alcohol doesn't only remove the taste of alcohol, but somehow additionally damages the overall beer taste and makes it inferior).

Those terms you use, "damage" and "inferior", are of course, subjective, relative, and circumstantial, rather than absolute.

When I used to drink a lot of beer, I might have agreed with their sentiment, since I would mostly be drinking because I wanted the effect of the alcohol.

But since I stopped drinking alcohol, after several months I found, to my surprise, that a zero alcohol beer can be quite a pleasant experience. The taste reminded me of what I used to like about drinking beer with friends, whilst the differences helped me to stay connected to my new found appreciation of clarity.

Beer has a incredible variety of tastes. Don't compare alcohol free beers with the alcoholic beers of the same brand, just view it as a separate family of beers. Try some and pick your favorite.

I've been sampling non-alcoholic beers recently. A few of the brands taste pretty good. I like Athletic Brewing, and the Heineken is good for what it is.

I switched to decaf from regular because regular made me too anxious. I can't tell the difference in terms of taste. Both taste great to me.

Wait ... but ... why? (in jest)

I understand why, though some of us think of decaf "coffee", much the same way others view white "chocolate". At some point, the thing you modified it to be, isn't representative of the original thing. IMO, it should not be called coffee or chocolate, even with a descriptive adjective up front.

This is a minor nit to pick, but still, for those of us with a strong love of (addition to) coffee (or chocolate), its an important distinction.

The flavour is the same

They're both still coffee and chocolate, though. That reminds me of my college roommate who tried to argue that gelato isn't ice cream, using light beer vs dark beer as an analogy!

TIL gelato isn't ice cream. I'm from Italy, where "ice cream" is the translation of gelato, and by that I mean the sweet and icy milk-based stuff people eat during the summer, however you English speakers decide call it.

I drink decaf tea because I like drinking tea but caffeine messes with my heart these days.

:-)

> I understand why, though some of us think of decaf "coffee", much the same way others view white "chocolate".1

Had a cardiovascular adventure some time ago. Caffeine was involved, and so I don't have. I agree decaf is a poor substitute, as is white, but they are all I can get.

If you try to define what is or is not coffee (or chocolate, milk, meat, ...) using its composition you'll end up with a lot of ambiguous and incorrect rules.

The correct way to solve this is to remember that language is an imprecise medium to transmit ideas. White chocolate is chocolate because people consider it chocolate, not the other way around.

Maybe your goal is to stain your teeth, and you don't particularly appreciate the drug's effects/addiction.

I want the opposite. Caffeine without the taste of coffee.

You're in luck, caffeine pills cost pennies and are readily available at many strengths.

You can also buy straight caffeine powder to try to make your own drinks. I made a few attempts at creating my own energy drinks with my Sodastream, flavoring, and caffeine powder... it never quite worked though. The powder just tastes like powder, and you can drink it straight with water if you just want the caffeine kick.

Tea?

Link seems dead now

Still up for me but here's an archive: