What's the difference between multiple infusions with the same leaves
vs one infusion with the same amount of tea, the same total amount of
water (sum of the multiple infusions), same total steep time (sum of
the multiple infusions), and, as much as possible, holding the
temperature constant?

For example:

Trial Tea Water Infusions Temp
1 8 g 20 oz 3 x 1 minute 180
2 8 g 60 oz 1 x 3 minutes 180

The only differences I can see a

1. The temperature cannot be exactly the same unless it is done on a
heating element. I could start the longer steep slightly hotter so
that the average temperature is the same.

2. The leaves get "shocked" multiple times going from room temperature
(or maybe refrigerated) to 180 or so.

3. Something (probably not good) happens to the leaves while sitting
between steeps.

It seems (to me) like 8 grams of tea in 60 oz of water would be way
too weak, but then that third steep should also be way too weak (and
maybe it is).

This looks like a job for Engineer Man. ;-)

On Aug 27, 11:13*pm, Square Peg > wrote:
> What's the difference between multiple infusions with the same leaves
> vs one infusion with the same amount of tea, the same total amount of
> water (sum of the multiple infusions), same total steep time (sum of
> the multiple infusions), and, as much as possible, holding the
> temperature constant?
>
> For example:
>
> Trial *Tea * Water * * Infusions * * *Temp
> * 1 * *8 g * 20 oz * 3 x 1 minute * * 180
> * 2 * *8 g * 60 oz * 1 x 3 minutes * *180
>
> The only differences I can see a
>
> 1. The temperature cannot be exactly the same unless it is done on a
> heating element. I could start the longer steep slightly hotter so
> that the average temperature is the same.
>
> 2. The leaves get "shocked" multiple times going from room temperature
> (or maybe refrigerated) to 180 or so.
>
> 3. Something (probably not good) happens to the leaves while sitting
> between steeps.
>
> It seems (to me) like 8 grams of tea in 60 oz of water would be way
> too weak, but then that third steep should also be way too weak (and
> maybe it is).
>
> This looks like a job for Engineer Man. ;-)


One thing not in your equation: caffeine. The quantity of cafeine
releases will not be the same one.

Each tea is different. I have more then 40 tea at home and for most of
them I will not use the same quantity, time and temp of water. Some
tea you can just do one batch and after that it lost the taste, and
some you can do up to three batchs (and increasing the time of
infusion). But for each batch, less caffeine will be involve and it
will taste more and more less (will taste more water).

Best way to know it. Try it. That's what I do.

Michel
Tea Amator spending around 1000-2000$ per year in tea
Moscou, Russia

On Sat, 30 Aug 2008 12:43:53 -0700 (PDT), wrote:

>On Aug 27, 11:13*pm, Square Peg > wrote:
>> What's the difference between multiple infusions with the same leaves
>> vs one infusion with the same amount of tea, the same total amount of
>> water (sum of the multiple infusions), same total steep time (sum of
>> the multiple infusions), and, as much as possible, holding the
>> temperature constant?
>>
>> For example:
>>
>> Trial *Tea * Water * * Infusions * * *Temp
>> * 1 * *8 g * 20 oz * 3 x 1 minute * * 180
>> * 2 * *8 g * 60 oz * 1 x 3 minutes * *180
>>
>> The only differences I can see a
>>
>> 1. The temperature cannot be exactly the same unless it is done on a
>> heating element. I could start the longer steep slightly hotter so
>> that the average temperature is the same.
>>
>> 2. The leaves get "shocked" multiple times going from room temperature
>> (or maybe refrigerated) to 180 or so.
>>
>> 3. Something (probably not good) happens to the leaves while sitting
>> between steeps.
>>
>> It seems (to me) like 8 grams of tea in 60 oz of water would be way
>> too weak, but then that third steep should also be way too weak (and
>> maybe it is).
>>
>> This looks like a job for Engineer Man. ;-)
>
>
>One thing not in your equation: caffeine. The quantity of cafeine
>releases will not be the same one.

Good point. I guess I wasn't focused on the caffeine because (a) I
don't think it affects the *taste* much if at all, (b) I was mainly
interested in the bitterness, and (c) I seem to be almost completely
immune to caffeine. ;-)

>Each tea is different. I have more then 40 tea at home and for most of
>them I will not use the same quantity, time and temp of water. Some
>tea you can just do one batch and after that it lost the taste, and
>some you can do up to three batchs (and increasing the time of
>infusion). But for each batch, less caffeine will be involve and it
>will taste more and more less (will taste more water).

My main purpose was the bitterness that you get from steeping too
long. It seemed odd to me that a tea would become bitter with one long
steeping, but that same tea could be steeped over and over again
without becoming bitter.

If a tea would become bitter if steeped for, say, 5 minutes, then I
would expect that same tea to become bitter on the fifth 1-minute
steeping (re-using the same leaves), assuming that the total amount of
tea and water and the steeping temperature are constant.

Square Peg > writes:

> On Sat, 30 Aug 2008 12:43:53 -0700 (PDT), wrote:
> >[...]
> >One thing not in your equation: caffeine. The quantity of cafeine
> >releases will not be the same one.
>
> Good point. I guess I wasn't focused on the caffeine because (a) I
> don't think it affects the *taste* much if at all, (b) I was mainly
> interested in the bitterness, and (c) I seem to be almost completely
> immune to caffeine. ;-)

But caffeine does affect the taste. Caffeine is quite bitter,
acutally. I suspect that's one reason colas have so much sugar.

> >Each tea is different. I have more then 40 tea at home and for most of
> >them I will not use the same quantity, time and temp of water. Some
> >tea you can just do one batch and after that it lost the taste, and
> >some you can do up to three batchs (and increasing the time of
> >infusion). But for each batch, less caffeine will be involve and it
> >will taste more and more less (will taste more water).
>
> My main purpose was the bitterness that you get from steeping too
> long. It seemed odd to me that a tea would become bitter with one long
> steeping, but that same tea could be steeped over and over again
> without becoming bitter.
>
> If a tea would become bitter if steeped for, say, 5 minutes, then I
> would expect that same tea to become bitter on the fifth 1-minute
> steeping (re-using the same leaves), assuming that the total amount of
> tea and water and the steeping temperature are constant.

Aren't you assuming that your sensory response to bitter substances is
linear with respect to their concentrations? And if you are, do you
have evidence for that?

/Lew
---
Lew Perin /
http://www.panix.com/~perin/babelcarp.html

On Sun, 31 Aug 2008 10:28:27 -0700, Square Peg >
wrote:

>On Sat, 30 Aug 2008 12:43:53 -0700 (PDT), wrote:
>
>>On Aug 27, 11:13*pm, Square Peg > wrote:
>>> What's the difference between multiple infusions with the same leaves
>>> vs one infusion with the same amount of tea, the same total amount of
>>> water (sum of the multiple infusions), same total steep time (sum of
>>> the multiple infusions), and, as much as possible, holding the
>>> temperature constant?
>>>
>>> For example:
>>>
>>> Trial *Tea * Water * * Infusions * * *Temp
>>> * 1 * *8 g * 20 oz * 3 x 1 minute * * 180
>>> * 2 * *8 g * 60 oz * 1 x 3 minutes * *180
>>>
>>> The only differences I can see a
>>>
>>> 1. The temperature cannot be exactly the same unless it is done on a
>>> heating element. I could start the longer steep slightly hotter so
>>> that the average temperature is the same.
>>>
>>> 2. The leaves get "shocked" multiple times going from room temperature
>>> (or maybe refrigerated) to 180 or so.
>>>
>>> 3. Something (probably not good) happens to the leaves while sitting
>>> between steeps.
>>>
>>> It seems (to me) like 8 grams of tea in 60 oz of water would be way
>>> too weak, but then that third steep should also be way too weak (and
>>> maybe it is).
>>>
>>> This looks like a job for Engineer Man. ;-)
>>
>>
>>One thing not in your equation: caffeine. The quantity of cafeine
>>releases will not be the same one.
>
>Good point. I guess I wasn't focused on the caffeine because (a) I
>don't think it affects the *taste* much if at all, (b) I was mainly
>interested in the bitterness, and (c) I seem to be almost completely
>immune to caffeine. ;-)
>
>>Each tea is different. I have more then 40 tea at home and for most of
>>them I will not use the same quantity, time and temp of water. Some
>>tea you can just do one batch and after that it lost the taste, and
>>some you can do up to three batchs (and increasing the time of
>>infusion). But for each batch, less caffeine will be involve and it
>>will taste more and more less (will taste more water).
>
>My main purpose was the bitterness that you get from steeping too
>long. It seemed odd to me that a tea would become bitter with one long
>steeping, but that same tea could be steeped over and over again
>without becoming bitter.
>
>If a tea would become bitter if steeped for, say, 5 minutes, then I
>would expect that same tea to become bitter on the fifth 1-minute
>steeping (re-using the same leaves), assuming that the total amount of
>tea and water and the steeping temperature are constant.

I think you have to look at what happens to tea in the first minute of
infusion.

Must be leaves start to unfurl and a succession of chemical reactions
start. Nothing like an even disbursement of particulates (a colloidal
state?) could occur for a time, depending on the form the tea leaf is
in to begin with, its manufacturing process, age, water temp, etc..

An analogy is what happens to ground coffee, which I understand is
supposed to be allowed to release its flavors after absorbing the
water and its "buds" open. One coffee maker I had was just a glass
container and filter holder in an hourglass shape, and you were
supposed to apply a dampening amount of hot water to the coffee and
allow a few minutes before continuing with the immersion. It tasted
good, probably because a relatively large amount of coffee was used in
a relatively short time, and a moderately coarse grind and the chem
filter didn't allow the "muddy" taste you get with a fine grind.

So on the basis of taking enough time to allow the tea leaves to
unfurl and do their thing, I assume that the serial quick infusions
approach will blanket the good and bad possibilities, but ideally you
have to wait a bit. I know different teas require different
techniques of infusion, but still like my approach of using a quick
blanch before that first serious infusion. After that, I suppose the
tea leaves continue absorbing water, up to a point. bookburn

On 31 Aug 2008 16:24:27 -0400, Lewis Perin > wrote:

>Square Peg > writes:
>
>> On Sat, 30 Aug 2008 12:43:53 -0700 (PDT), wrote:
>> >[...]
>> >One thing not in your equation: caffeine. The quantity of cafeine
>> >releases will not be the same one.
>>
>> Good point. I guess I wasn't focused on the caffeine because (a) I
>> don't think it affects the *taste* much if at all, (b) I was mainly
>> interested in the bitterness, and (c) I seem to be almost completely
>> immune to caffeine. ;-)
>
>But caffeine does affect the taste. Caffeine is quite bitter,
>acutally. I suspect that's one reason colas have so much sugar.

You are correct. I should have checked that.

http://www.coffeefaq.com/site/node/17

>> >Each tea is different. I have more then 40 tea at home and for most of
>> >them I will not use the same quantity, time and temp of water. Some
>> >tea you can just do one batch and after that it lost the taste, and
>> >some you can do up to three batchs (and increasing the time of
>> >infusion). But for each batch, less caffeine will be involve and it
>> >will taste more and more less (will taste more water).
>>
>> My main purpose was the bitterness that you get from steeping too
>> long. It seemed odd to me that a tea would become bitter with one long
>> steeping, but that same tea could be steeped over and over again
>> without becoming bitter.
>>
>> If a tea would become bitter if steeped for, say, 5 minutes, then I
>> would expect that same tea to become bitter on the fifth 1-minute
>> steeping (re-using the same leaves), assuming that the total amount of
>> tea and water and the steeping temperature are constant.
>
>Aren't you assuming that your sensory response to bitter substances is
>linear with respect to their concentrations?

No, I don't think I am assuming that. In fact, I would think that a
linear response (correlation) would make my argument stronger.

I have read in many tea discussions that over-steeping (longer
steeping times) causes bitterness by increasing the tannins in the
liquor. If this is true, and it certainly seems to be, then the
tannins are not released until after some amounbt of time that varies
by the type of tea.

Let's say I steep a green tea for 3 minutes and it becomes bitter.
Then I steep another batch for 2 minutes (all other conditions the
same) and it is not bitter. I conclude that the tannins are mostly
released in that third minute.

Now what will happen if I were to resteep the leaves from the 2-minute
batch for another minute? I would think that it would be very bitter.

But there is a problem. The two steepings (2 minutes + 1 minute) are
not equivalent to the one 3-minute steeping. For one thing, the two
steepings produced twice as much tea from the same amount of leaves.

I think to make it equivalent, I need to decrease the water in the
two-step experiment. I am not sure if I should use half as much water
for each steeping or 2/3 as much for the first, since it is 2/3 of the
time.

I ran a few crude experiments with inconclusive results. I will trey
again when I get some free time. I know everyone is waiting with bated
breath for the results. ;-)

I think you are right on with the tannin theory. I seem to have a
vague and unscientific understanding from different sources that the
tannins may be released in larger amounts as the tea is steeped for
longer. One good reason to make short steeps instead of one long one
is if you mess up one of the steeps, you can still have another go at
a decent cup of tea. If you over-steep your leaves in one long steep
with more water you are stuck with a lot of undrinkable tea.

When I drink certain Chinese Oolong teas such as Wuyiyancha and
Dancong, I find that fewer leaves in more water wont give me the same
sort of flavour as using the same amount of water and making multiple
infusions. This may be partly a water temperature problem, though. I
ought to admit to my bias for small, multiple infusions, partly for
aesthetic reasons.

If you do increase the temperature of the larger steeping, you may
risk injuring your green tea.

The whole doesnt equal the sum of the parts. Tea solubles is much
more complex than just tannins.

Jim

PS Brown tannins bad, red tannins good

Square Peg wrote:
....a weak cup of tea taster better than a good cup of coffee...
> Let's say I steep a green tea for 3 minutes and it becomes bitter.
> Then I steep another batch for 2 minutes (all other conditions the
> same) and it is not bitter. I conclude that the tannins are mostly
> released in that third minute.

On Tue, 2 Sep 2008 05:40:37 -0700 (PDT), Xuancheng
> wrote:

>I think you are right on with the tannin theory.

I'm not sure I have a theory, just a bunch of questions.

>I seem to have a
>vague and unscientific understanding from different sources that the
>tannins may be released in larger amounts as the tea is steeped for
>longer.

If a X micrograms of tannins are released in a 5-minute steeping, then
I would expect the same amount of tannins to be released from five
1-minute steepings.

Now, if the 5-minute brew is with 500 ml of water and the five
1-minute brews are all each with 500 ml of water, then the tannins
will be diluted by a factor of 5 unless they are all released in the
final steeping. That's why I suggested 5 one-minute steepings in 100
ml of water.

>One good reason to make short steeps instead of one long one
>is if you mess up one of the steeps, you can still have another go at
>a decent cup of tea. If you over-steep your leaves in one long steep
>with more water you are stuck with a lot of undrinkable tea.

That's a point. However, I'd rather learn to do it right than
construct my method to allow for mistakes. ;-)

>When I drink certain Chinese Oolong teas such as Wuyiyancha and
>Dancong, I find that fewer leaves in more water wont give me the same
>sort of flavour as using the same amount of water and making multiple
>infusions. This may be partly a water temperature problem, though. I
>ought to admit to my bias for small, multiple infusions, partly for
>aesthetic reasons.

What's more aesthetic about one over the other?

>If you do increase the temperature of the larger steeping, you may
>risk injuring your green tea.

On Tue, 2 Sep 2008 07:23:55 -0700 (PDT), Space Cowboy
> wrote:

>The whole doesn't equal the sum of the parts.

Probably not. I am trying to understand how it is different and what
makes the difference.

>Tea solubles is much more complex than just tannins.

No doubt. I am not saying that tannins are the whole story. I'm
actually less interested in what the chemicals are, at this point,
than in what the results are.

>Jim
>
>PS Brown tannins bad, red tannins good
>
>Square Peg wrote:
>...a weak cup of tea taster better than a good cup of coffee...
>> Let's say I steep a green tea for 3 minutes and it becomes bitter.
>> Then I steep another batch for 2 minutes (all other conditions the
>> same) and it is not bitter. I conclude that the tannins are mostly
>> released in that third minute.

Think of tea as a food group.

Jim


Square Peg wrote:
> On Tue, 2 Sep 2008 07:23:55 -0700 (PDT), Space Cowboy
> > wrote:
>
> >The whole doesn't equal the sum of the parts.
>
> Probably not. I am trying to understand how it is different and what
> makes the difference.
>
> >Tea solubles is much more complex than just tannins.
>
> No doubt. I am not saying that tannins are the whole story. I'm
> actually less interested in what the chemicals are, at this point,
> than in what the results are.