Puerh Storage in Low Humidity

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


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Nov 25th, '09, 23:07
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Re: Puerh Storage in Low Humidity

by Chip » Nov 25th, '09, 23:07

... good to see Intuit is on the case ... :lol:

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Nov 26th, '09, 10:37
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Re: Puerh Storage in Low Humidity

by xogget » Nov 26th, '09, 10:37

Intuit wrote:>Bacteria have nothing on mold spores which can survive unusually angry environments.

Ha! You haven't met my extremophilic bacterial buddies.
http://en.wikipedia.org/wiki/Extremophiles

:lol:
Maybe storage in thermal vents is the next step in pu erh evolution

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Re: Puerh Storage in Low Humidity

by john.b » Nov 29th, '17, 05:22

I referred to this old thread in reviewing the issue again. It related to a separate discussion about framing humidity in absolute versus relative terms (as a proportion of water to air, by weight, instead of as a relative % of what the air will hold at that weight). That doesn't seem to get you very far, but it was interesting to consider it, and see it mapped out in psychrometric graphs.

Related to a vendor video about storage locations, and the wet and dry issue, I also added a section identifying climate conditions in Hong Kong, Malaysia, and Kunming.

http://teaintheancientworld.blogspot.co ... ative.html

Dec 1st, '17, 18:43
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Re: Puerh Storage in Low Humidity

by Cwyn » Dec 1st, '17, 18:43

The primary organisms responsible for aging of puerh tea in the first phase is Aspergillus Niger to break down the cell walls, and in the later phase, Rhizopus to sweeten the juices released by the cell wall breakdown. These organisms are fungi, not molds and not bacteria. Comparisons with beer or sourdough are not inaccurate, the fermentation here is that of fruits and vegetables with no starter additive.

Other bacteria or molds present are by-products providing carbon for the fungi which is why a well-aged puerh tea (or well-ripened) will have these byproducts consumed fully in the process, making the beverage consumable without ill effects, while a too dry or too humid aging environment can cause too little fungal activity, or too high mold or bacteria count. Just to be on the safe side, a boiling rinse is a good idea especially if we don't know where that newly-acquired puerh has been.

My best teacher is failure. I can attest to the loss of flavor and vitality in storing tea too dry following the cardboard box method recommended by Cloud some years ago. Even with a bowl of water, my drier environment resulted in flavor loss, even in my shou puerh. In more recent years, along with finding a better storage method I have been looking to fail on the higher humidity end with tea samples in order to learn more. For me, the teas that do best under the higher humidity are, not surprising, the highly bitter, compressed and smoky factory teas.

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Re: Puerh Storage in Low Humidity

by jayinhk » Dec 1st, '17, 23:59

Cwyn wrote:For me, the teas that do best under the higher humidity are, not surprising, the highly bitter, compressed and smoky factory teas.
This is why traditional storage was a thing! I still feel those old recipes best suit the climate here as the leaves are more resistant to decomposition over the long term. Fancier stuff can sometimes lose a little too much complexity during rapid decomposition. I used to worry that my summer air conditioning here in HK was enough to disrupt my pu and added a shot glass of water to my bedroom storage cabinet; I now know there is absolutely no need for that, even with air conditioning.

Dec 13th, '17, 14:08
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Re: Puerh Storage in Low Humidity

by Cwyn » Dec 13th, '17, 14:08

Exactly, the tea and the storage climate are a match. I get so disturbed when I see blanket generalizations about teas without storage taken into account, for example "factory recipes are better," without the understanding that these are best aged in a more humid setting, or vice versa, that floral teas are better or worse when the subtle flavors get killed by that same storage. How the tea is treated matters, whether that tea is an enjoyable drink or not.

The same blanket generalizations are applied to the storage, "humid storage is bad," well no it is perfect for a bitter, smoky and compressed tea. Or "dry storage is bad," well a certain drier storage may actually be best for more delicately flavored tea.

Also, we just don't know enough about what works over 20-30 years. Our examples of fine tea over the long haul are not well documented enough, and current storage set ups are too new to date. We know more about failure at this point than success. At some point in the future, this will get turned around as more data gets shared.

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Re: Puerh Storage in Low Humidity

by Zared » Dec 13th, '17, 16:46

I suspect fresh tea bought from Kunming isn't gonna improve much in 5-10yrs for most people in the US. Its one reason I've been hesitant to buy anything to age that young or isn't enjoyable now. I'd rather not realize in 5yrs that I wasted $5000+ on stuff that I still don't want to drink. Though I'm thinking it's time to take the chance with some humid stored teas that already have a leg up.

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Re: Puerh Storage in Low Humidity

by Rui » Dec 14th, '17, 03:07

An example of a very low humidity environment not working for pu'er storage is that I have wasted enough 100gms cakes, samples and tuo's stored here in the office. After a short while they taste like straw with most of the aroma lost and that is due to the low humidity around here.

At the moment I am sitting in a office at 24.5 degrees C which should go up as the day goes on to around 26 degrees C. I believe that is excellent for pu'er storage.

The problem lies in the low humidity level. It is now 23% relative humidity and that will drop to around 20% later in the day.

Solution: I have a couple of cigar humidifiers in my largest drawer with 72% humidity packs. These humidors are opened every couple of days to 'freshen' up the air inside. So far this has worked very well and the teas are maturing faster than at home where we have not got such high temperatures.

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Re: Puerh Storage in Low Humidity

by xiaguanfanboy » Mar 20th, '18, 15:41

I have been storing my puer in Germany the last 3 years.
Stored in clay jars and fabric bags in a old cupboard.

Humidity inside the jars did always stay between 50~65% RH.

The Tea still smells good.
Taste is not boring or sour at all.
The Tea did age a aswell.

I wouldn't use cigar humidifier inside my jars or a “pumidor“ . Did read a lot comments alreadY that everything will just taste the same after a while.


I recommend people use a room humidifier in case of heavy aircon/heater usage.

I wasnt at home from Nov. Till end of Feb. Expect of some airing out my place once a week nobody looked after my place.
So the Tea went through wet/cold and dry/cold periods and was “hibernating“ after i came back home.
After 3 weeks normal living conditions the Tea smeels a bit stronger.. tastes fine.

Increasing humidity by alot while maintaining low temperatures in Europe will only increase the risk of mold.
And maybe the Tea will give away a stronger scent. But without the right temperature the aging process will be slow anyway.

But slow aging isnt that bad.. just think about how slow scottish whisky ages compared to indian whisky.

Sent from my BLN-L21 using Tapatalk


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Re: Puerh Storage in Low Humidity

by orange. » May 17th, '22, 15:32

Lots of people who did not grow up with traditionally-stored puerh tea don't like that kind of taste profile. It is also widely talked about in Taiwan and in China that this taste profile comes from (too much) microbial activity. That's probably why in Taiwan and in China, dry-stored tea sells at a premium. If they must choose between dry/astringent notes or wet/humid storage flavors, they would probably go for the dry/astringent. Or stay away from Puerh all together. The good news is that we are lucky to have choices.

Also, once you have developed a liking for the dry-stored taste profile, the next thing you may be asking is how to prevent microbes from having wild parties in your cakes.

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Re: Puerh Storage in Low Humidity

by fraveydank » May 19th, '22, 18:00

orange. wrote: Lots of people who did not grow up with traditionally-stored puerh tea don't like that kind of taste profile. It is also widely talked about in Taiwan and in China that this taste profile comes from (too much) microbial activity. That's probably why in Taiwan and in China, dry-stored tea sells at a premium. If they must choose between dry/astringent notes or wet/humid storage flavors, they would probably go for the dry/astringent. Or stay away from Puerh all together. The good news is that we are lucky to have the choices.

Also, once you develop a liking for the dry-stored taste profile, the next thing you may be asking is how to prevent microbes from having wild parties in your cakes.
Really, the problem here in North America is that a lot of places have way too much air conditioning. We are pretty light on it, and even so our house generally hovers between 20% and 40% RH. At that rate, I’m relatively certain the tea will dry out enough to lose a lot of flavor.

I’ve been testing out Pelican cases as an option for smaller, more modular humidity controlled containers (similar to the clay jar idea, but a lot more portable and sturdy, since I don’t have loads and loads of space. I made a thread here on it, which I’ll be updating with results periodically.

The nice thing about the Boveda packs is that they have ones for lower humidity as well for other purposes, such as musical instruments and, uh, “tea”. Right now I’m trying at 65-69% and seeing what comes out, but I have thoughts for some of the larger, longer-term storage with lower humidity just to maintain the flavor and a slow age.

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Re: Puerh Storage in Low Humidity

by fraveydank » Feb 20th, '23, 10:54

fraveydank wrote: I’ve been testing out Pelican cases as an option for smaller, more modular humidity controlled containers (similar to the clay jar idea, but a lot more portable and sturdy, since I don’t have loads and loads of space. I made a thread here on it, which I’ll be updating with results periodically.

The nice thing about the Boveda packs is that they have ones for lower humidity as well for other purposes, such as musical instruments and, uh, “tea”. Right now I’m trying at 65-69% and seeing what comes out, but I have thoughts for some of the larger, longer-term storage with lower humidity just to maintain the flavor and a slow age.
So I’m coming up on about a year since I started this, and the results have been pretty great, humidity-wise (obviously it’s a bit too early to tell if it’s helped the aging a lot, but it hasn’t dried out or imparted any off-flavors to the tea so far). Here’s an example humidity plot from one of my more recent builds with a 69% 320-gram Boveda pack (a few gaps where I went too long without dumping the hygrometer data, it only has about a 2-week storage).
2A140961-AE55-40D5-8E89-BFC4F694852D.png
Thermo/hygrometer reading for 6 months in 1525 case
This is in a Pelican 1525 Air case, which I’ve found to be a pretty good size for something I don’t expect to have huge loads of (this one is for heicha, and it seems I did undershoot the size a bit because it is chock full now). The 1557 Air cases are full treasure-chest size and excellent for larger quantities, but I recently switched the hygrometers out in them and due to app limitations I don’t have a longer history.

I’ll have more details on my main thread about this, including pictures of this particular build.

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