What ages Pu?

[Bubba_tea]

Here's a topic... anyone know what actually does the aging in pu? I would guess it's either/or bacteria or fungus (yeast) - as in sourdough or alcohol. I was interested as to the other Medusa thread and oxygen vs. air flow.

With reports of some of you getting stoned on pu I wouldn't be suprised if there's some interesting by-products of the maturation process... shhhhh...

[silverneedles]

certain humidity + temperature that facilitates fungal growth (instead of bacteria)
(and the fungi that "infect" the storage room then "infect" the tea leaf)

unlike black tea which is fermented by its own enzymes, in puerh the tea leaf enzymes are destroyed, and ferments under the presence of fungal enzymes.

one recent study*
over a 50 day period,
on maocha because it says the tea is in piles, found

Aspergillus species (MPT1 a relative of Aspergillus Niger) eats up from the tea polyphenols
then started growing Blastobotrys adeninivorans

* Characteristic fungi observed in the fermentation process for Puer tea, International Journal of Food Microbiology 124 (2008) 199-203.

[Wesli]

unlike black tea which is fermented...

Except for the fact that black tea undergoes no fermentation.

I believe what "ages" pu-erh (other than time ) is a combination of bacteria, fungi, and mold.

BTW, SilverNeedles, doesn't it sound like it's the shu fermentation process they're talking about?

[brandon]

I collect spores, mold, and fungus.

[Proinsias]

time?

[silverneedles]

oxidation fermentation shermemntation

oops yeah, i was skip reading
for the real juicy stuff: the DNA sequences of the fungus CTCGCCCTCTCTT j/k ...

there's mention of tea being splashed with water etc
it was shu processing indeed

but this is just 1 factory/room, other factories could have different microbial populations at work...

[scruffmcgruff]

I collect spores, mold, and fungus.

ROFL

[Bubba_tea]

LOL - nice, Dr. Spengler - lay off the fungal toxins..

[VinceBLG]

I think people confuse oxydation with fermentation.

[ABx]

I think people confuse oxydation with fermentation.

They traditionally called it 'fermentation' in the tea industry, and the term still gets used a lot. My guess is that it's probably a hold-over from before they had the means to find out that it was oxidation and not actual fermentation.

The thing about puerh aging is that nobody really knows for sure; maybe someday someone will do some hard science. The types and amount of bacteria, mold, and fungus seem to depend mostly on storage conditions and not on age.

[Wesli]

maybe someday someone will do some hard science. The types and amount of bacteria, mold, and fungus...

Then they can create a probiotic product that has all these goodies in them. Perhaps a spray that you use on all new pieces before putting them into storage.

[ABx]

maybe someday someone will do some hard science. The types and amount of bacteria, mold, and fungus...

Then they can create a probiotic product that has all these goodies in them. Perhaps a spray that you use on all new pieces before putting them into storage.

That general sentiment is why I'm actually surprised that they haven't done more. Once they figure out exactly how it ages they could find ways to make "real" aged puerh a lot faster - whether it's enhanced oxidation or something with the organisms and/or enzymes. Granted, bacterial colonies can only grow as large as their nutrient store will supply (which is why I mention the levels of microorganisms depend on storage rather than age).

I would actually like that because we could get good puerh for a lot cheaper, and the real aged stuff would actually be worth even more (collectors and connoisseurs would tout true aging as better because of the characteristics from the storage environment, but the speed-aged stuff would hold us over).

[Salsero]

the speed-aged stuff

Sounds suspiciously like shu. Maybe time is part of the equation.