Aged pu'er air too dry

One of the intentionally aged teas, Pu-Erh has a loyal following.

Mar 10th 16 4:53 pm
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Aged pu'er air too dry

by oolongtimenosee » Mar 10th 16 4:53 pm

I know someone who was given some shang pu cakes (Chi Tse Beeng Cha) around 9 years ago. They kept them in a closet in Canada, but because of the low humidity, they taste about the same as they did when they were new. They would like to know if they can re-start the aging process by increasing the humidity level or is it too late? If it's not too late, any suggestions for keeping the humidity at a good level for aging?

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Mar 10th 16 5:28 pm
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Re: Aged pu'er air too dry

by Drax » Mar 10th 16 5:28 pm

You can find lots of discussions in this part of the forum about humidity and storage. There are lots of options! (search for pumidor, humidity, storage)

As for attempting to re-start the aging process, that topic hasn't come up too frequently, from what I recall. It'd be interesting to get Cwyn's take on it. :D

I see potentially two broad options: restart alone, or restart with help.

Restart alone. You can just try putting the dead cakes into a more humid (and warm) environment. However, the critters involved with aging the tea may all be dead from the last few years of dry storage, so nothing might happen. Then again, they may have just done dormant, and so humidity and warmth may revive them, and you'd be off to the races again after some time of restart.

Restart with help. The other option: buy a couple of properly stored cakes (they wouldn't have to be very old), and store them with your old and dry cakes. Put them all together in a place with proper humidity and warmth. Then, theoretically, the live cakes could revive the dead cakes. I'm not sure how effective that process might really be (if the dead cakes are really dense, will outside critters be able to penetrate to the same extent as if it had been originally?).

Again, I don't recall that we've had hard evidence either way. Maybe somebody else has, and will share it (or remind me, as the case may be). :D

Mar 11th 16 2:26 am
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Re: Aged pu'er air too dry

by oolongtimenosee » Mar 11th 16 2:26 am

Drax wrote:You can find lots of discussions in this part of the forum about humidity and storage. There are lots of options! (search for pumidor, humidity, storage)

As for attempting to re-start the aging process, that topic hasn't come up too frequently, from what I recall. It'd be interesting to get Cwyn's take on it. :D

I see potentially two broad options: restart alone, or restart with help.

Restart alone. You can just try putting the dead cakes into a more humid (and warm) environment. However, the critters involved with aging the tea may all be dead from the last few years of dry storage, so nothing might happen. Then again, they may have just done dormant, and so humidity and warmth may revive them, and you'd be off to the races again after some time of restart.

Restart with help. The other option: buy a couple of properly stored cakes (they wouldn't have to be very old), and store them with your old and dry cakes. Put them all together in a place with proper humidity and warmth. Then, theoretically, the live cakes could revive the dead cakes. I'm not sure how effective that process might really be (if the dead cakes are really dense, will outside critters be able to penetrate to the same extent as if it had been originally?).

Again, I don't recall that we've had hard evidence either way. Maybe somebody else has, and will share it (or remind me, as the case may be). :D
Thanks for the reply, Pu'er is the tea I'm least familiar with, but am growing to like a lot. Interesting suggestion of adding a properly aged cake to sit with the others, sounds like the same process in making Yogurt (add a little yogurt to milk, provide right environment = more yogurt). I wonder if I could add a new shang pu cake as well (wouldn't it also have the same micro-organisms?).

Mar 11th 16 2:45 am
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Re: Aged pu'er air too dry

by mr mopu » Mar 11th 16 2:45 am

oolongtimenosee wrote:
Drax wrote:You can find lots of discussions in this part of the forum about humidity and storage. There are lots of options! (search for pumidor, humidity, storage)

As for attempting to re-start the aging process, that topic hasn't come up too frequently, from what I recall. It'd be interesting to get Cwyn's take on it. :D

I see potentially two broad options: restart alone, or restart with help.

Restart alone. You can just try putting the dead cakes into a more humid (and warm) environment. However, the critters involved with aging the tea may all be dead from the last few years of dry storage, so nothing might happen. Then again, they may have just done dormant, and so humidity and warmth may revive them, and you'd be off to the races again after some time of restart.

Restart with help. The other option: buy a couple of properly stored cakes (they wouldn't have to be very old), and store them with your old and dry cakes. Put them all together in a place with proper humidity and warmth. Then, theoretically, the live cakes could revive the dead cakes. I'm not sure how effective that process might really be (if the dead cakes are really dense, will outside critters be able to penetrate to the same extent as if it had been originally?).

Again, I don't recall that we've had hard evidence either way. Maybe somebody else has, and will share it (or remind me, as the case may be). :D
Thanks for the reply, Pu'er is the tea I'm least familiar with, but am growing to like a lot. Interesting suggestion of adding a properly aged cake to sit with the others, sounds like the same process in making Yogurt (add a little yogurt to milk, provide right environment = more yogurt). I wonder if I could add a new shang pu cake as well (wouldn't it also have the same micro-organisms?).
You could send them to me for proper storage minus a small percentage as a fee...The jump start with a new sheng is a good idea though.

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Re: Aged pu'er air too dry

by Drax » Mar 11th 16 3:01 am

oolongtimenosee wrote:Thanks for the reply, Pu'er is the tea I'm least familiar with, but am growing to like a lot. Interesting suggestion of adding a properly aged cake to sit with the others, sounds like the same process in making Yogurt (add a little yogurt to milk, provide right environment = more yogurt). I wonder if I could add a new shang pu cake as well (wouldn't it also have the same micro-organisms?).
Yes, I think you could add a new cake, too. But... here's where things start to get a lot more into speculation for me (that is, I don't know that I've seen definitive answers anywhere, only best guesses).

Teas from different parts of Yunnan (or elsewhere) probably have different mixtures of micro-organisms. Sort of like with yogurt, there are different strains. And the same with cheese (e.g., making of blue cheese, depends on the organisms in the particular cave). And if so, what does it mean to mix different cakes together? If you kept teas from different regions separate, they would have different tastes. But if you put cakes together, do they become more similar to each other? Or at least, more similar than if they had been kept separate? I don't know...

For what it's worth, I don't worry about that latter possibility. I've put most of my sheng together in the same cabinet, and they're cakes (and bricks and tuos) of many, many different regions.

Mar 11th 16 3:44 am
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Re: Aged pu'er air too dry

by mr mopu » Mar 11th 16 3:44 am

Drax wrote:
oolongtimenosee wrote:Thanks for the reply, Pu'er is the tea I'm least familiar with, but am growing to like a lot. Interesting suggestion of adding a properly aged cake to sit with the others, sounds like the same process in making Yogurt (add a little yogurt to milk, provide right environment = more yogurt). I wonder if I could add a new shang pu cake as well (wouldn't it also have the same micro-organisms?).
Yes, I think you could add a new cake, too. But... here's where things start to get a lot more into speculation for me (that is, I don't know that I've seen definitive answers anywhere, only best guesses).

Teas from different parts of Yunnan (or elsewhere) probably have different mixtures of micro-organisms. Sort of like with yogurt, there are different strains. And the same with cheese (e.g., making of blue cheese, depends on the organisms in the particular cave). And if so, what does it mean to mix different cakes together? If you kept teas from different regions separate, they would have different tastes. But if you put cakes together, do they become more similar to each other? Or at least, more similar than if they had been kept separate? I don't know...

For what it's worth, I don't worry about that latter possibility. I've put most of my sheng together in the same cabinet, and they're cakes (and bricks and tuos) of many, many different regions.
I will concur as to having the same producer of the tea you are trying to revive. I have different set ups for YS, W2T, Crimson, Mandala and then Da Yi and HaiWan.

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Re: Aged pu'er air too dry

by Tead Off » Mar 11th 16 3:46 am

Is there really any truth to the complete dying off of the micro-organisms that are needed for the fermentation process?

Mar 11th 16 5:05 am
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Re: Aged pu'er air too dry

by mr mopu » Mar 11th 16 5:05 am

Tead Off wrote:Is there really any truth to the complete dying off of the micro-organisms that are needed for the fermentation process?
I am not sure if they die off or just slow down. I try to not take any chances if I don't have to.
I wish I had your climate conditions Tead Off.

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Mar 11th 16 5:12 am
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Re: Aged pu'er air too dry

by Tead Off » Mar 11th 16 5:12 am

mr mopu wrote:
Tead Off wrote:Is there really any truth to the complete dying off of the micro-organisms that are needed for the fermentation process?
I am not sure if they die off or just slow down. I try to not take any chances if I don't have to.
I wish I had your climate conditions Tead Off.
Our climate may be good for puerh, but there are a lot of trade-offs in other areas. I get sick of the heat.

Slowing down, I understand. Dying off? Not so sure. Hopefully, a more scientific minded poster could chime in on this.

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Re: Aged pu'er air too dry

by Drax » Mar 11th 16 10:59 am

Tead Off wrote:Is there really any truth to the complete dying off of the micro-organisms that are needed for the fermentation process?
That's why I said I hadn't seen evidence either way, and that's also why I laid out two possibilities. I do not recall seeing any actual information other than speculation.

I would love to see some more solid information on the topic.

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Re: Aged pu'er air too dry

by Tead Off » Mar 11th 16 11:40 am

Drax wrote:
Tead Off wrote:Is there really any truth to the complete dying off of the micro-organisms that are needed for the fermentation process?
That's why I said I hadn't seen evidence either way, and that's also why I laid out two possibilities. I do not recall seeing any actual information other than speculation.

I would love to see some more solid information on the topic.
Sorry to repeat what you had said originally. :D

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Re: Aged pu'er air too dry

by Drax » Mar 11th 16 12:07 pm

It's all good! Hopefully it highlights our strong desire to know more.

Hrm, what we really need is a botanist? Maybe a biologist? Entropy embrace was a great source for such things, but she has been around less. I'll do some hunting and see what I can dig up...

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Re: Aged pu'er air too dry

by jayinhk » Mar 11th 16 12:51 pm

Many of the microorganisms involved are airborne and you'll introduce new species with adequate exposure and moisture. Your tea is a substrate for all kinds of microflora...and possibly fauna if the bugs get into it, as they do here in Asia!

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Re: Aged pu'er air too dry

by oolongtimenosee » Mar 13th 16 3:48 am

Interesting. I checked wikipedia to see what actually causes the fermentation and their sources attribute the most important microbe involved to a kind of fungus related to black mould :shock: (but not toxic) https://en.wikipedia.org/wiki/Pu-erh_tea#Fermentation

The other microbes they claim can vary depending on factory and region.

As suggested, it seems I could grab one of their cakes (they've offered to give me a couple), increase humidity and pack it with another sheng pu'er cake to be safe.

Humidity levels aren't a problem where I'm living (South China/Hong Kong). Mould is one of the easiest things to grow here. :lol:

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Re: Aged pu'er air too dry

by entropyembrace » Mar 18th 16 3:50 am

I'm still around enough that I read most of the active threads :)

I do have some clarifications on the wikipedia link:

first all of the papers there are in reference to pile fermented shu pu-erh, not to long term aging of sheng pu-erh that you were asking about at the beginning of the thread.

Also the high abundance of Aspergillus mold in the studies that the wiki cites has a very high chance of being an artifact of the technique they used to identify the microbes in the fermentation piles. Quantitative direct sequencing studies place some kinds of bacteria and yeast as being more abundant. Also we really have no idea how each group of microbes contributes to the flavour of the tea.

The microbes in aged sheng pu-erh are almost certainly different because of the very different conditions but there's very little research into what they are that I'm aware of...

So can dry conditions kill off all of the microbes in your pu-erh? I think no way! Many bacteria and fungi are able to form spores in stressful conditions which will lay dormant until conditions improve. Any spore formers in your tea will be able to survive bad conditions. You might lose some microbial diversity if non-spore forming species are killed off. I have no idea if that would be important or not.