A Serving of Tea

I'm sure they mean a cup of the liquor.

Even though it's only a question of the liquor, there is vagueness in lots of published numbers when it comes to steep times and temperatures, as well as multiple steeps. (Multiple steeps are important with regard to caffeine when the temperature is relatively low and the first steep is fairly swift, which is the way most people who like green teas do it.)

/Lew

It also stands to reason that substances other than caffeine are affected by multiple steeps. For example, I simply cannot believe that the anti-oxidants in a cup of liquor from the 3rd steep are close to the same that they were for the 1st steep.

Randy

You're sure? That just doesn't make sense to me. There is no way there is that much caffeine (or polyphenol etc..) in one teaspoon of green tea leaf. In that same literature we read that black tea has more caffeine than green, but most people re-steep green tea many more times than black (at least as far as I know, I really only drink green tea so some black tea drinkers out there feel free to correct me) so the green tea drinkers would be getting TONS while the black tea drinkers would get less.

mabey I asked an impossible question, there might be just too many variables to get any kind of accurate answer unless you test the exact leaf in question.

Sorry, I'm confused now. There's no way there is *how much* caffeine in a teaspoon of leaf?

What I've seen of that literature suffers from a lack of clarity and uniformity as to exactly what was done to yield the liquor they measured. But I wouldn't exclude the possibility that 5 minutes of boiling leaves (typical for black) might yield more caffeine than 3 short, relatively cool steeps (of green.)

/Lew

Most of what I have read says there is roughly 35 mg caffeine in a "cup" of green tea. So I am wondering if this number applies to a serving of the leaf or is it applied to one of the 5 or so "cups" you can get from a serving of that leaf? I can't believe there is 35 mg of caffiene multiplied by 5 cups in one teaspoon of leaf. We all know that most of the caffiene comes out early in the steeping, and the rest of the stuff (amino acids, polyphenols etc..) comes out in later steeps, but I am wondering about the total amounts. When I drink green I get many steeps, usually at least 5, while black tea gives me two steeps at best.

Ah-ha. So you think mabey they are steeping green tea for 5 min. in boiling water in the lab? That could be, that way they are treating all teas the same way (I still can't imagine a japanese scientist for example pouring boiling water on some sencha and letting it sit there for five min. seems a little funny even in the lab) I don't think I have read anything that talked about the difference in steeping temperature with regard to caffiene. What have you heard about this?

In most of what I've read, it isn't clear what they did to extract the caffeine.

Agreed.

Probably some of them are doing that.

There are probably some young Japanese scientists by now who grew up on Coca-Cola and coffee.

I think you can find something about this from past threads in this group by checking Google Groups. The way I remember it, it comes down to the fact that caffeine, like many - nearly all? - substances, is more soluble in water as temperature rises. I'm sure Dog Ma will slap me down if I'm wrong here!

/Lew

Lewis Perin

True all around, except that I'd never slap so distinguished a gentleman - who also, given the diversity of his Oriental education, is probably both kinds of gong-fu master.

Personally, I've gotten so annoyed with all the the pseudo-scientific assertions that I've removed most of my former posts on this and related subjects. Whatever one says, someone (often less informed) disagrees, so they didn't seem a useful addition to the archive. Perhaps one of us will borrow a lab for a week, do the definitive series of experiments, and end the argument. Amazing that it hasn't been done already, and published on the Web.

-DM

You mean you removed those posts from Google Groups? I sure hope not: that would leave the less-informed posts unchallenged.

/Lew

Green tea has the same amount of caffeine as black.

Before I knew better, I brewed green tea for 5-6 minutes. It makes a bitter tea with quite a bit of kick, but it takes alot of will to drink it. Proper brewing is MUCH better.

My understanding is if you do the traditional "gongfu cha" brewing method you get most of the caffeine out during the first steeping, subsequent steepings have less caffeine. I have no idea about polyphenols, but I suspect it's similar, as the polyphenols in green tea are 95 percent absorbed by the water in about 3 minutes.

Also, some decaffination processes remove polyphenols, but there is disagreement on this point in the literature I have read.

Maybe some of the more justified assertions could be covered in the FAQ... Of course, we don't want the FAQ to put us out of business.. heh

Steve