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A chemist explains the chemistry behind decaf coffee

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Re: A chemist explains the chemistry behind decaf coffee

#171

Earlier quoted context omitted.

Did taking molybdenum improve metabolism of caffeine in your case? Did you have blood markers checked? For me, some values like GPT/GGT are in fact increased for unknown reasons. I recently and unsuccessfuly researched ways to participate in studies, as I'd like to understand why I can't eat chocolate or drink coffee anymore.. I'm slightly concerned other toxins wouldn't be metabolized as well either, leading to earl…

I took 1 mg of molybdenum daily for about 3 weeks and then tested out drinking coffee. By this point I had tried many other interventions that did not help. I wasn't expecting the molybdenum to help but figured it was worth a shot since it was about $6 for a bottle. After the fourth day of drinking coffee, it was clear that something had changed; the coffee was no longer the issue that it had been. I'm now able to en…

Thanks a lot! Just ordered a bottle and will give it a try

Re: A chemist explains the chemistry behind decaf coffee

#172

Earlier quoted context omitted.

There are stimulating compounds in coffee other than caffeine, so I've pondered that people who find decaf stimulating may be reacting to some of these other compounds. Another consideration is that people seem to often report that coffee is more stimulating than caffeine pills, even if the amount of caffeine is similar.

"There are stimulating compounds in coffee other than caffeine,…" OK, that makes sense and I'm not surprised. I claim no expertise in coffee chemistry but I'd guess there'd likely be small amounts of other xanthines including xanthine, theophyline, theobromine [we ought to stop using that confusing name] and perhaps others. Are you referring to these or another class of drugs altogether? You know, your mention that o…

I'm no coffee chemistry expert either, but the following article indicates that the main adenosine receptor antagonists are caffeine, theophylline, and theobromine, all of which are found in coffee, tea, and chocolate (https://en.wikipedia.org/wiki/Adenosine_receptor). These three are all considered purines and therefore molybdenum would be involved in breaking them down. All three also have a diuretic effect (1) and Theobromine "shows strong diuretic effects" (2). That leads me to wonder if the ratio of these three varies significantly between coffees. I'm not sure but found one paper that shows that it does in cocoa (3), so perhaps it does in coffee also (there's probably research on coffee about this and I just didn't look hard enough).

(1) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4383091 (2) http://medical-technologies.eu/upload/1.effects_of_coffee_al... (3) https://www.sciencedirect.com/science/article/pii/S030881460...

Re: A chemist explains the chemistry behind decaf coffee

#173

A good video explanation from James Hoffman: https://youtu.be/yYTSdlOdkn0 And a quick follow up: https://youtu.be/IszQ2JR3Olc

I can’t recommend James Hoffmann’s channel enough - he’s such a passionate coffee guy who’s just as happy teaching what he knows about coffee to anyone and everyone. (He also won a world barista championship back in the day, too.) I daresay he’s even got me into coffee.

The video on how he won it is very good and probably would be interesting for any competitive sport or craft. Recommend that.

Re: A chemist explains the chemistry behind decaf coffee

#174

Earlier quoted context omitted.

"There are stimulating compounds in coffee other than caffeine,…" OK, that makes sense and I'm not surprised. I claim no expertise in coffee chemistry but I'd guess there'd likely be small amounts of other xanthines including xanthine, theophyline, theobromine [we ought to stop using that confusing name] and perhaps others. Are you referring to these or another class of drugs altogether? You know, your mention that o…

I'm no coffee chemistry expert either, but the following article indicates that the main adenosine receptor antagonists are caffeine, theophylline, and theobromine, all of which are found in coffee, tea, and chocolate ( https://en.wikipedia.org/wiki/Adenosine_receptor ). These three are all considered purines and therefore molybdenum would be involved in breaking them down. All three also have a diuretic effect (1) a…

Thanks for the references. Just had an initial look and I'll return to them shortly. I was already aware the action of xanthine class drugs is centered on the adenosine receptors but I've little deeper knowledge of the subject, drugs and their biological action isn't my field so I'll have to take the documents slowly.

However, I've already noted in (2) a statement under Theobromine that it's a strong diuretic. That's interesting but what does strong mean here? I dislike simple-notion words in papers unless they're quantified (they require numbers against them).

That said, that's not a criticism of the paper having just glanced at it, and it has lots of other interesting stuff I'll need to read in detail. What's particularly relevant about the theobromine entry is this mention of the molecule's strong diuretic effect. When I made my point towards the end of my comment that that particular coffee 'likely had much more than the usual trace of theophyline in it', I deliberately left out reference to theobromine because I'd seen references that it was biologically less active than either theophyline and caffeine.

What was implied was that when evaluating the effects of coffee that theobromine was essentially considered irrelevant because it wasn't as biologically potent as either theophyline and caffeine and that its concentration in coffee is considerably lower than either of the other two.

Perhaps the earlier reference (which I've to locate again) was referring to theobromine's psychotropic effects rather than its diuretic effects. I'll now have to review and revise my understanding of common xanthines to correct my misunderstandings.

As someone who's not professionally involved in this field I sometimes think I'm a little mad for allowing my curiosity to get the better of me. :-)

Re: A chemist explains the chemistry behind decaf coffee

#175
post #43

I'd like to talk a bit more about the cheapest and most common process here. They state that ethyl acetate is below the FDA limits and therefore safe. For a start ethyl acetate is still pretty bad but it's not the cheapest. 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 solve…

> You know what else is a solvent for decaffeinating coffee? Benzene. Please don't spread misinformation. Benzene was the original solvent used 120 years ago in Germany when decaf was first invented. It did not last long as the dangers of benzine became apparent. There have been several generations of solvents used in the over one century since then and benzine has not been a part of the decaf world in a very long ti…

"Coffee in moderation is good for you, caffeine or not."

As I pointed out in another post a few days ago we consume many plant products that contain chemicals and toxins that are harmful some of which are very toxic yet we do not remove them from our food.

Plants especially make these dangerous toxins to deter or kill insects that eat them, I went on to point out that caffeine is one of the most innocuous of these toxins and that some common ones are considerably worse.

In a response to a poster who quoted the negative effects of different amounts of caffeine from Wiki (1-1.5g and >5g respectively) I then listed a comparative scaling with a toxin found in the common vegetable spinach, specifically oxalic acid. To quote:

"…If you scaled up oxalic acid daily doses in the same ratio as for the caffeine example then in the first instance the person would almost undoubtedly have kidney stones. In the second example the person would be dead. Right, at that dose Popeye's spinach meal would almost certainly have killed him.

At least the 'caffeinated' person, whilst off his head, would likely be still alive."

The reason why we remove caffeine from coffee is twofold, the first is that it's comparatively easy to do so when compared with toxins found in other foodstuffs (for instance, to remove mercury in fish would be inordinately difficult); the second is that caffeine has noticeable psychotropic effects that manifest shortly after consumption and that they are obvious worries some people to a considerable extent while others enjoy those effects—and many even depend on them to start their day.

Thus, as with alcohol, caffeine has both strong emotive and sociological aspects to it. It's why caffeine features high in popular culture, everyone knows of and talks about its effects.

On the other hand, despite the fact that it's dangerous and that its toxic effects are dire and insidious, oxalic acid is hardly ever mentioned in popular culture specifically because its effects are not as immediately obvious as those of caffeine. As they take a much longer time to manifest than those of caffeine, it's much harder to draw a connection between them and their cause.

Moreover, it's rather ironic that the popular cartoon character Popeye came to prominence because of a principal property of oxalic acid, its extreme bitterness. Oxalic acid's bitterness contributes to the taste of spinach and kids find it strong and overpowering because of their immature palates. So Popeye making fun of kids who don't eat spinach seemed a good strategy to get them to eat it (I've no idea whether the strategy worked as I liked spinach from when I was first introduced to it).

In small doses oxalic acid can be consumed reasonably frequently without harm as it's in many of our common vegetables, although that's not necessarily so with all vegetables such as spinach, rhubarb and beetroot which contain it in much larger amounts. Consumption of these vegetables in large amounts or even eating them frequently can lead to adverse effects such kidney stones. Also, the acid's oxalate metabolites are very insoluble and form crystals that can actually damage the kidneys.

(I have a two-kilo container of oxalic acid which I use to remove rust from tools and to bleach stains from wood and it's very conspicuously labeled 'Poison' in big letters.)

You say caffeine is not good for you, which implies it's dangerous. As I've shown I reckon the evidence supports my position that it's not as dangerous as many other toxins that we encounter in our food, like it or not we have to consume them to stay alive.

Chemical technology has given many the choice whether or not to consume caffeine but I'd venture it does not give them the right to criticize or single it out over and above the many other toxic molecules we unavoidably encounter on a daily basis.

To do so is not only counterproductive but also it's not in the best interests of others, it also shows that one is misinformed.

_

BTW, the solubility of caffeine in benzene is poor when compared to other better alternatives, it's another good reason not to use it for the extraction process.

Moreover, nothing I've said above applies to benzine, it's a nasty, dangerous compound to be avoided. That said, it's a curious phenomenon why so many useful compounds contain benzene rings many of which aren't toxic—even life depends on the benzene ring. Nevertheless, others based on the ring are so dangerous that they leave benzene's toxicity for dead.

Re: A chemist explains the chemistry behind decaf coffee

#176
post #137

Earlier quoted context omitted.

Most people in this world don't eat enough protein (cca 65g daily for average human IIRC) and way too many carbs, hence a lot of civilization diseases. Or ratio protein : carbs (ideally complex) : fats (ideally unsaturated) is bad long term. But its true that not healthy food that has some additional protein mixed in ain't magically healthy.

> don't eat enough protein (cca 65g daily for average human IIRC) and way too many carbs, hence a lot of civilization diseases We as a specie haven't eaten as many protein as today since the invention of agriculture millennia ago, so idk what you mean by “civilization diseases” but if you mean diabetes and such, then it's clearly wrong. We're currently eating too much and too much sugar though.

There's apparently scientific studies that show how animals as well as humans tend to continue eating until they've satisfied a mostly fixed daily need for protein, mostly regardless of _what kind_ of food they're eating.

Now if people choose a diet low in protein/calories ratio, they'll have a tendency to ingest more calories than people who eat protein rich diets. Try eating eating 300 g of cheese/meat/tofu in one meal, it'll be difficult. Eating 300 g of chips/fries is something many people can absolutely do, if the chips aren't too salty.

One significant difference between our modern western lives and the lives of people tens to hundreds of years ago is IMO that people back then quite automatically used up all the carb calories of their comparably protein diluted diet because life required much more physical activity and came with less home heating than today. Today, most people will just not expend much of the caloric energy of carb rich diets and thus develop metabolic diseases and such.

A carb rich diet is usually fine as long as you expend the energy via physical activity.

Re: A chemist explains the chemistry behind decaf coffee

#177
post #14

I thought about buying a supercritical CO2 extraction machine from Alibaba and having a small business around making decaf beans for roasters, but the numbers didn't work out great. I believe it was around $20k usd for the medium sized ones.

Is this written up anywhere? I.e. anywhere that walks thru a sample business model?

Well it's not too complex. Say $25k for the machine amortized over 5 years is about $400/mo. Let's say $500. Cost of goods would be around $7.50/lb for some nice unroasted beans. Let's say you sell for $10/lb. Fixed costs would be rent ($5k?), utilities (1k?) and whatever other costs to package etc. not even touching salaries. So at $2.50/lb revenue you'd have to process and sell 2,400 lbs per month just to break even on fixed costs. That's a lot...

Re: A chemist explains the chemistry behind decaf coffee

#178
post #176

Earlier quoted context omitted.

> don't eat enough protein (cca 65g daily for average human IIRC) and way too many carbs, hence a lot of civilization diseases We as a specie haven't eaten as many protein as today since the invention of agriculture millennia ago, so idk what you mean by “civilization diseases” but if you mean diabetes and such, then it's clearly wrong. We're currently eating too much and too much sugar though.

There's apparently scientific studies that show how animals as well as humans tend to continue eating until they've satisfied a mostly fixed daily need for protein, mostly regardless of _what kind_ of food they're eating. Now if people choose a diet low in protein/calories ratio, they'll have a tendency to ingest more calories than people who eat protein rich diets. Try eating eating 300 g of cheese/meat/tofu in one…

> Try eating eating 300 g of cheese/meat/tofu in one meal, it'll be difficult. Eating 300 g of chips/fries is something many people can absolutely do

I don't know where you get the idea that eating 300g of meat is difficult …

> A carb rich diet is usually fine as long as you expend the energy via physical activity.

Any balanced diet is fine if you ingest no more energy than you spend, which is exactly what I said: people today are eating too much.

Re: A chemist explains the chemistry behind decaf coffee

#179

Earlier quoted context omitted.

This is like what happens with milk fat. I was surprised to see whole milk cost more, and I found out that it's because the fat skimmed off is used for other products.

Same with yogurt. Whey protein isolate goes for $11/lb, which is ridiculous pricing as a side note.

[deleted]

Re: A chemist explains the chemistry behind decaf coffee

#180
post #176

Earlier quoted context omitted.

There's apparently scientific studies that show how animals as well as humans tend to continue eating until they've satisfied a mostly fixed daily need for protein, mostly regardless of _what kind_ of food they're eating. Now if people choose a diet low in protein/calories ratio, they'll have a tendency to ingest more calories than people who eat protein rich diets. Try eating eating 300 g of cheese/meat/tofu in one…

> Try eating eating 300 g of cheese/meat/tofu in one meal, it'll be difficult. Eating 300 g of chips/fries is something many people can absolutely do I don't know where you get the idea that eating 300g of meat is difficult … > A carb rich diet is usually fine as long as you expend the energy via physical activity. Any balanced diet is fine if you ingest no more energy than you spend, which is exactly what I said: pe…

> .. don't know where you get the idea that eating 300g of meat is difficult.

You're right, 300 g of meat isn't much of a challenge. The more appropriate comparison would be between 300 g of chips and an equal amount of calories in some protein rich food like meat. That should be much more challenging.

> .. people today are eating too much.

Yeah, the important question is: why are they eating too much?

I assume that a lot of it is unintentional. Overeating mostly happens because people aren't aware of a few simple mechanisms or are misunderstanding them, not because the world is hard. Mechanisms which they could quite easily use to overeat less or avoid it altogether, instead of falling prey to them.

Just telling people that they're eating to much doesn't help in any way. People need to know why and how they can quite easily change it.

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