Michael Plant, who has enriched this group with a diversity of wit, wisdom
and actual useful information that would do credit to Dr. Johnson, has
admitted to employing a twist on the usual metronomic or monotonically
lengthening interval between gong-fu steeps. Viz.: he'll do a pot the usual
way, immediately take a second extraction, then let the pot rest until both
cups have been consumed. Or something like that; he can explain better.

While discovering aberrant behavior at this locus is not in itself
surprising, the merits of this technique might be. First, allow me to assert
a few presuppositions, unproven by "Science" AFAIK:

1. Many people seem to imagine tea brewing as though a pill or bolus of
matter were smoothly dissolving. This is definitely not the case. Even the
refinement of considering some goop smeared into the pores of a sponge
doesn't quite make it.

2. While dry leaf may equilibrate thermally in a second or two, full
hydration probably takes closer to a minute.

2a. On the former point, BTW and contrary to popular myth, the mass of wet
leaves does not cool at any appreciable rate between steeps. (A full pot
cools even less.) Most of the cooling that people report is a single
step-drop due to thermal capacity of un-tempered vessels. All that mythology
about how various vessels hold heat during brewing is bunkum, IMO. The
dominant factor in open containers is evaporative loss; nothing else can
compare in magnitude. Sorry to be so opinionated, but people waste so much
effort worrying about this non-phenomenon.

3. Substances are extracted from the leaf by multiple mechanisms on multiple
length scales, from direct displacement off polymer surfaces and out of
interstices, to diffusion and percolation through pores in the leaf
structure, to gross convective mixing in the bulk.

4. The rate of these processes depends intimately on the local environment.
This means hydration on the nano- and micro-scales, and mechanical
separation at the leaf-in-water level. It also means that relative
extraction rates of diverse substances may be very different in the first
few steeps, before the "dilute solution" approximation applies - especially
within leaf pores and in the polymer matrix.

5. So instead of (1), a more accurate representation might be similar to the
"coupled compartment" model used in dive computers to estimate tissue
nitrogen loading, further modified to accommodate Case 1 and Case 2
diffusion (ie., diffusion that is linear or history-dependent) as hydration
is achieved, and non-linearities early on due to the concentration of
extractables that themselves affect solvent properties.

I know, that was all obvious. Here's the fun part: I've actually done a few
dozen crude experiments with Michael's approach, and confirmed that once the
leaf is fully hydrated (usually after one or two steeps), extraction
continues at about the same rate whether the pot is full or "empty." This is
not surprising: once the rate of extraction has declined to the point that
there is little solvent change due to solutes, there is more than enough
water in and on the leaf to "carry" what's coming out of those notional
compartments. There just lacks any bulk fluid to carry it away. Since the
pot innards stay hot, the intersteep hiatus is actually "stewing" those
valuable leaves.

Michael's method helps a lot, and is instructive as regards change in flavor
balance (as distinct from overall intensity) with oversteeping. What I found
works even better, though I can rarely be bothered, is to make that fast
second steep with much cooler water, just at comfortable drinking
temperature. This washes off the ready-to-go goodies, and leaves the leaves
in a calm mood to await a new poaching after I've consumed both cups. Makes
a more uniform series of steeps. It also means that in addition to the 300
pots that Michael has demonstrated are necessary for any serious tea
drinker, you will also need a second Zojirushi.

-DM

"Dog Ma 1" (reply w/o spam) writes:

[...Between gongfu steeps, you're still making tea...]

I'm so glad you wrote up your insights, DM.

Michael's method helps a lot, and is instructive as regards change
in flavor balance (as distinct from overall intensity) with
oversteeping. What I found works even better, though I can rarely be
bothered, is to make that fast second steep with much cooler water,
just at comfortable drinking temperature. This washes off the
ready-to-go goodies, and leaves the leaves in a calm mood to await a
new poaching after I've consumed both cups. Makes a more uniform
series of steeps. It also means that in addition to the 300 pots
that Michael has demonstrated are necessary for any serious tea
drinker, you will also need a second Zojirushi.

Or, you can just brew tea like an old Chinese guy, spacing the time
between quick steeps according to when the next "inter-steep steep" is
ready to be flushed with hot water. One thing I'd like to know is:
does a traditional gongfu master consciously think in terms of when
it's time to do the next steep, or is it just implicit knowledge?

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

"Dog Ma 1" (reply w/o spam) writes:

[...Between gongfu steeps, you're still making tea...]

I'm so glad you wrote up your insights, DM.

Michael's method helps a lot, and is instructive as regards change
in flavor balance (as distinct from overall intensity) with
oversteeping. What I found works even better, though I can rarely be
bothered, is to make that fast second steep with much cooler water,
just at comfortable drinking temperature. This washes off the
ready-to-go goodies, and leaves the leaves in a calm mood to await a
new poaching after I've consumed both cups. Makes a more uniform
series of steeps. It also means that in addition to the 300 pots
that Michael has demonstrated are necessary for any serious tea
drinker, you will also need a second Zojirushi.

Or, you can just brew tea like an old Chinese guy, spacing the time
between quick steeps according to when the next "inter-steep steep" is
ready to be flushed with hot water. One thing I'd like to know is:
does a traditional gongfu master consciously think in terms of when
it's time to do the next steep, or is it just implicit knowledge?

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

Dog Ma /30/04
reply w/o spam

Michael Plant, who has enriched this group with a diversity of wit, wisdom
and actual useful information that would do credit to Dr. Johnson, has
admitted to employing a twist on the usual metronomic or monotonically
lengthening interval between gong-fu steeps. Viz.: he'll do a pot the usual
way, immediately take a second extraction, then let the pot rest until both
cups have been consumed. Or something like that; he can explain better.

I hardly recognize myself. Please don't applaud; just throw tea. I merely
found that received and conventional wisdom that suggests increasing the
steep time for each successive steep of gungfu tea often leads to
unpleasantly strong and overpowering tea. Conversely, I found that
ultra-rapid steeps -- following "rest" periods of some minutes as the damp
leaves await their next hot inundation -- work great, releasing more good
tea liquor than you might otherwise expect. However, the ultra-rapid steep,
followed on the heels of a previous steep, yields an unacceptably weak cup.
The conclusion is that something important is happening while the damp
leaves are resting. Now to read the rest of Dog Ma's post, where he probably
explains this better than I could.

While discovering aberrant behavior at this locus is not in itself
surprising, the merits of this technique might be. First, allow me to assert
a few presuppositions, unproven by "Science" AFAIK:

1. Many people seem to imagine tea brewing as though a pill or bolus of
matter were smoothly dissolving. This is definitely not the case. Even the
refinement of considering some goop smeared into the pores of a sponge
doesn't quite make it.

Those of us who own cats are quite familiar with the nature of boli of
matter.

2. While dry leaf may equilibrate thermally in a second or two, full
hydration probably takes closer to a minute.

2a. On the former point, BTW and contrary to popular myth, the mass of wet
leaves does not cool at any appreciable rate between steeps. (A full pot
cools even less.) Most of the cooling that people report is a single
step-drop due to thermal capacity of un-tempered vessels. All that mythology
about how various vessels hold heat during brewing is bunkum, IMO. The
dominant factor in open containers is evaporative loss; nothing else can
compare in magnitude. Sorry to be so opinionated, but people waste so much
effort worrying about this non-phenomenon.

Bunkum: My favorite form of science. So, in practice, to increase or
decrease the rate of cooling going on in there, cover or uncover the pot,
right?

3. Substances are extracted from the leaf by multiple mechanisms on multiple
length scales, from direct displacement off polymer surfaces and out of
interstices, to diffusion and percolation through pores in the leaf
structure, to gross convective mixing in the bulk.

Polymer tea leaves: There's an idea whose time has come. Somebody's gonna
make a bundle, mark my words.

4. The rate of these processes depends intimately on the local environment.
This means hydration on the nano- and micro-scales, and mechanical
separation at the leaf-in-water level. It also means that relative
extraction rates of diverse substances may be very different in the first
few steeps, before the "dilute solution" approximation applies - especially
within leaf pores and in the polymer matrix.

Something tells me polymer ain't plastic any more.

5. So instead of (1), a more accurate representation might be similar to the
"coupled compartment" model used in dive computers to estimate tissue
nitrogen loading, further modified to accommodate Case 1 and Case 2
diffusion (ie., diffusion that is linear or history-dependent) as hydration
is achieved, and non-linearities early on due to the concentration of
extractables that themselves affect solvent properties.

I know, that was all obvious. Here's the fun part: I've actually done a few
dozen crude experiments with Michael's approach, and confirmed that once the
leaf is fully hydrated (usually after one or two steeps), extraction
continues at about the same rate whether the pot is full or "empty."

Yup. Toldya.

This is
not surprising: once the rate of extraction has declined to the point that
there is little solvent change due to solutes, there is more than enough
water in and on the leaf to "carry" what's coming out of those notional
compartments. There just lacks any bulk fluid to carry it away. Since the
pot innards stay hot, the intersteep hiatus is actually "stewing" those
valuable leaves.

Which is a good thing or a bad thing depending on the type of tea we're
"stewing". Oolongs are the tea of choice here, IMO.

Michael's method helps a lot, and is instructive as regards change in flavor
balance (as distinct from overall intensity) with oversteeping. What I found
works even better, though I can rarely be bothered, is to make that fast
second steep with much cooler water, just at comfortable drinking
temperature. This washes off the ready-to-go goodies, and leaves the leaves
in a calm mood to await a new poaching after I've consumed both cups. Makes
a more uniform series of steeps.

I see your point here of course, but uniformity is not what I'm after. Tea
is more interesting when each steep is a surprise. Lately and curiously,
I've found that in gungfuing Oolongs aroma sometimes diminishes and
intensifies through various steeps, which is not what I would expect; I'd
expect aroma to continue to diminish, and having diminished, disappear
entirely. Maybe it's something I'm doing wrong. Or right. Or something.

It also means that in addition to the 300
pots that Michael has demonstrated are necessary for any serious tea
drinker, you will also need a second Zojirushi.

And I will second that. In fact, I often do use two.

Thanks for explicating, Dog Ma.

Michael

There's something I should have remembered in writing my original
response to Dog Ma's illuminating post:

Dog's main point was that, once the leaves in a brewing vessel get
soaked with hot water, the steeping will continue even after the
liquor is poured off. He explores some of the consequences, limiting
himself to gongfu brewing.

But his insight applies to *all* multi-steep brewing, and I want to
call people's attention to its consequences for brewing green tea.
Many of us have learned to do a second steep of green tea that is
shorter than the first. For delicate senchas, we basically pour off
the liquor of the second steep as fast as possible. Now the reason
for this is clear: the second steep just dilutes the highly
concentrated liquor - the zavarka, Sasha? - that's already been brewed
*inside* the leaves.

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

Now the reason
for this is clear: the second steep just dilutes the highly
concentrated liquor - the zavarka, Sasha? - that's already been brewed
*inside* the leaves.

/Lew
---

Zets rait, tovarisch! And the world tea bourguosee iz trying to hide thiz
from ze peoplez.
Tea drinkers of the world, unite!

Sasha.