how much caffeine in decaf coffee/tea? varies?

I assume some caffeine may remain in decaf coffee? How much does this vary? Do some kinds have less? I.e., is there less caf in “milder” tasting coffees or is that unrelated?

What about teas without caffeine? Is this due to the plant used or is it removed in process?

While I am asking: are there other stimulants in coffee or tea besides caf?

I ask because I have benign essential tremor (or whatever it is now called), and over the past year it seems to have comeback with a vengance.

I believe decaf has to be at least 97% caffeine free, according to the FDA. Herbal teas, made from herbs and spices, are naturally caffeine-free(although some may have other, natural stimulants, depending on the ingredients). Black, white, green, and red teas all have varying amounts of caffeine, unless they go through the de-caffeinating process.

I was doing some research on this not to long ago, and this was the best page I found. It contains caffeine content from both caffeinated and decaffeinated beverages. It’s from a medical site and uses the proper sources from the FDA.

That link you posted goes to a virus/Trojan horse threat assessment report, BigT. I didn’t check the site carefully, I just removed the link since it wasn’t what you said it was.

Oops. I’d just used that link in ATMB. I meant to link here:

The other three are derived in various ways from the actual tea plant, and so do contain caffeine, but red tea is a completely different plant, and to my understanding does not contain any.

On to the OP’s question about other stimulants, I imagine that at least some would contain theobromine, a chemical related to caffeine and which is the major stimulant in chocolate.

I checked before I posted, and it has about 4 or 7% caffeine.

Lighter roasts generally have higher caffeine content than darker roasts because moisture is lost during the roasting process and with that moisture goes caffeine. But extraction method is also a factor and espresso extracts more caffeine from the coffee than drip brewing; however, one doesn’t generally consume espresso in the same amounts as drip coffee and, therefore, consumes less caffeine. Robusta, a less expensive, hardier coffee species, contains about twice as much caffeine as Arabica (gourmet) coffee.

If you’re extremely sensitive to caffeine, none of that probably makes a difference and you should stick to decaffeinated coffee, which are not completely free of caffeine, but is considerably less than any non-decaffeinated coffee, regardless of roast, species, or extraction.

Rooibos (A.K.A. Red Tea) is naturally caffeine free. Since this is GQ, let me provide citations (other than the wholesalers I buy from and the labeling on my packages of rooibos):

If I remember correctly, it isn’t even “Tea” as in the plant which black, oolong, green, white teas come from.

Rooibos come from a bush in africa, and is a member of the legume family.

I stand corrected. The site I checked was wrong. Red tea has no caffeine.

ETA: Ahhh, I see, the first link from Wikipedia for Red Tea leads to here Camellia sinensis - Wikipedia

Which does contain caffeine. The second link is the correct Rooibos.

Some confusion might result from the fact that “red tea” is used to refer to two different things. It commonly refers to Rooibos, as already discussed. But, in my experience, what many Chinese tea shops in the U.S. sell under the name “red tea” is, in fact, what Westerners know as “black tea.” And this does have caffeine.

No good cite, only this Wikipedia disambiguation link.

:dubious: Bwuh?

Evaporating off the water = lose caffeine? That doesn’t jive with physics.

If anything, I would posit that the longer roasting time thermally degrades the (somewhat) complex caffeine structure. The process of driving off water is going to do virtually nothing to the non-volatile compounds left behind.

Modern decaffeination processes use supercritical CO2 (which is a gas but behaves like a liquid) and are very efficient at extracting caffeine. I’d be surprised if “decaf” had any measurable physiological effects are normal consumption levels.

I stand corrected.

Actually, it’s neither. There are an infinite number of different kinds of fluids; gases and liquids just happen to be a good approximation for a lot of the fluids we have everyday experience of. A gas is a fluid with the equation of state PV = nkT, while a liquid is a fluid with the equation of state rho = constant, but supercritical CO[sub]2[/sub] doesn’t have either of those equations of state, so it’s neither.