low-tech pumidor

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Jun 24th, '13, 20:31
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low-tech pumidor

by SFLouis » Jun 24th, '13, 20:31

I'm experimenting with a low-tech storage method using a humidification technique I learned from people who grow mushrooms indoors. I bought a huge, lidded bucket made of food-grade plastic from a beer-brewing supply house and filled up the bottom 3 inches or so with wet perlite. Perlite is a gardening soil material, basically a type of volcanic mineral that is very porous and wicks moisture into the air very effectively. It is cheap. On top of the perlite, I placed a bunch of ceramic items that I'm not using, and then piled up puerh cakes on top of that until the bucket was full. At the top, I put a small, digital device that measures temperature and humidity, and I sealed the lid over the top of the bucket. There is a small hole in the lid, but I've plugged it with a broken bit of cork from a wine bottle. Then I set up a small, office-type space heater about 1 foot away, aimed at the bucket, on the low setting. This setup was very inexpensive, and very easy to make. I did this about 2 weeks ago, and upon opening up the bucket and checking on things, the temperature read 82 degrees farenheit, with humidity at 84%. There was no condensation visible on the sides of the bucket, but that would probably be something to watch out for. The fragrance coming out of the bucket, when opened, was very strong and smelled good to me.

I know I'll have to add more water at some point, but for now I think I'm going to just sort of check on it once every week or two.

Jun 24th, '13, 20:48
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Re: low-tech pumidor

by shah82 » Jun 24th, '13, 20:48

I...

I think...

you'd need to...uh...


Maybe think about this a little more?


I mean, a setup for growing mushrooms...



Maybe tea and mushrooms have, roughly some of the same requirements...



But not completely.

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Jun 24th, '13, 21:33
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Re: low-tech pumidor

by TokyoB » Jun 24th, '13, 21:33

Or put another way, I really think you're rolling the dice and sooner or later you'll roll snake eyes (= mold!!!).

82F and 84% humidity would really scare me... :shock:

Jun 24th, '13, 21:56
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Re: low-tech pumidor

by mr mopu » Jun 24th, '13, 21:56

i have a pumidor setup in an old refrigerator. The humidity in the freezer part for sheng is kept at 70%. The lower fridge part for shu is only at 64%. I think the humidity over 70% may be dangerous in having the possibility of mold. Most tea vendors that I know usually recommend humidity lower than what I currently have.

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Jun 24th, '13, 22:10
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Re: low-tech pumidor

by tenuki » Jun 24th, '13, 22:10

Doing the same thing but using humidification beads (hold at steady 65% humidity) and maybe a bit of ventilation. still dialing it it, will post picts and instructions when it's working to my satisfaction.

Jun 24th, '13, 22:30
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Re: low-tech pumidor

by SFLouis » Jun 24th, '13, 22:30

Hm. Well, I don't feel like it's all that risky. I mean, it's very easy for me to open up the bucket and take stuff out and have a look at it. If I find mold, I can easily make some adjustments. To be honest, tiny specks of mold I've found on wetter stored samples have not bothered me, and if I were to find a substantial moldy patch all of a sudden, I would certainly remove it, but I'd still drink the rest of the cake eventually. I'm certainly not storing cakes for resale. I have checked several of the cakes pretty closely, and there is no mold present so far. Maybe I should build a chamber specifically for the purpose of generating the highest possible humidity and put one of my old 'tuition' cakes in there so I can find out exactly how high the humidity has to be in order to produce mold.

It's actually not that far of a jump to apply mycological humidification techniques to the purpose of storing tea. In either situation, one is trying to manipulate the temperature and humidity so that it will favor the growth of fungi. When you are trying to age tea, what you are trying to do is in fact fungal and bacterial fermentation, right?

Jun 24th, '13, 22:33
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Re: low-tech pumidor

by shah82 » Jun 24th, '13, 22:33

I can promise you that the setup as it currently looks to be is not likely to be a success to you or anyone else.

Jun 24th, '13, 22:47
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Re: low-tech pumidor

by SFLouis » Jun 24th, '13, 22:47

... and as to the 'requirements' for tea storage... It's not as if there were some universally agreed upon standard. Storage is a matter upon which there is very little agreement among puerh enthusiasts. Searching around the internets, I can find some who say that humidity in the low 80s is 'dry' or 'natural' storage, while I can also find others who feel it's too wet. I intend to find out for myself. If I find mold I promise to post it.

Over the last couple of years I've tasted a bunch of samples (from vendors & shops who shall remain nameless and don't you ask me 'cause I'm not telling) that were very bland and metallic-tasting because (I suspect) they had been stored for too long in open air & low humidity/temp. I have had mid-2000's teas that had been wetter stored in hot, extremely humid places in southeast asia and it resulted in what I can only describe as awesomeness.

Jun 24th, '13, 23:07
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Re: low-tech pumidor

by shah82 » Jun 24th, '13, 23:07

That awesomeness? Generally part of a climate.

Moreover, I'm not actually wearing the no-wet-storage cap. I'm wearing the don't-kill-me cap. As in, you won't have safe to drink tea, no matter what it tastes like. That set up is perfect for dangerous microbial growths.

And going back to that awesomeness? That wasn't typically done without losses due to spoilage and breakage. Those losses are with attentive monitoring of the warehouse situation.

Lastly, virtually all well done traditional storage has a drying out period of some years to reduce the funk to pleasant black-eyed-peas taste. You gunna know just how much of that seriously humid storage is enough before you put it on the shelves?

Jun 24th, '13, 23:17
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Re: low-tech pumidor

by SFLouis » Jun 24th, '13, 23:17

I promise to have someone let you know if I die ;)

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Jun 24th, '13, 23:35
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Re: low-tech pumidor

by Tead Off » Jun 24th, '13, 23:35

SFLouis wrote:... and as to the 'requirements' for tea storage... It's not as if there were some universally agreed upon standard. Storage is a matter upon which there is very little agreement among puerh enthusiasts. Searching around the internets, I can find some who say that humidity in the low 80s is 'dry' or 'natural' storage, while I can also find others who feel it's too wet. I intend to find out for myself. If I find mold I promise to post it.

Over the last couple of years I've tasted a bunch of samples (from vendors & shops who shall remain nameless and don't you ask me 'cause I'm not telling) that were very bland and metallic-tasting because (I suspect) they had been stored for too long in open air & low humidity/temp. I have had mid-2000's teas that had been wetter stored in hot, extremely humid places in southeast asia and it resulted in what I can only describe as awesomeness.
I think Bangkok in general, is a good climate for aging Puerh. But, even here, we don't have 80% humidity. That is stifling.

Perhaps there is a trade-off between prolonged exposure to high humidity. There is probably an acceleration in the beginning years for aging, but I can't see this being a good long-term aging environment. The natural fermentation process has already been established by the processors of the tea. That natural fermentation process needs to be cultivated over time and protected from exaggerated climate spikes, IMO. But, good luck with your experiment.

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Jun 24th, '13, 23:38
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Re: low-tech pumidor

by Tead Off » Jun 24th, '13, 23:38

Just to paint a picture here of the climate today at 10:30am, it is rainy season and the sky is full of clouds building up for the showers that will come at some point. The humidity is 66.4% and the temp is 31c.

Jun 25th, '13, 00:13
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Re: low-tech pumidor

by SFLouis » Jun 25th, '13, 00:13

Weatherbase.com has Bangkok's monthly average relative humidity ranges from 49-68 when measured in the evening, but it ranges from 84 to 92% (yikes) when measured in the morning. So it does indeed get WAY over 80%. In fact, the morning average relative humidity is lowest in December, and even then it is 84%, and that IS stifling. Wow.

http://www.weatherbase.com/weather/weat ... C+Thailand

According to this 7-day forecast, the humidity in Bangkok tends to fluctuate between the high 40's and the mid 80's during the course of a day: http://www.tititudorancea.com/z/weather_don_muang.htm

Your point is still very valid. Unfluctuating humidity over 80% is a very different thing from humidity that may fluctuate by as much as 30% during the course of a day. I will check my cakes very carefully. Thanks for the good luck wishes!

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Jun 25th, '13, 01:06
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Re: low-tech pumidor

by Tead Off » Jun 25th, '13, 01:06

Add an amount of ventilation or wind flow to the humidity of 80% and it becomes very different than no airflow at 80% humidity. Many variables. Also, not every part of Bangkok will be the same temp/humidity. This is a huge city. It tends to rain in different parts of the city, rarely raining everywhere at the same time. Heat and sun will dissipate humidity. Some parts of the city will get more sunshine than others. It is always warm here, though. :D

Jun 25th, '13, 07:01
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Re: low-tech pumidor

by mr mopu » Jun 25th, '13, 07:01

Tead Off wrote:Add an amount of ventilation or wind flow to the humidity of 80% and it becomes very different than no airflow at 80% humidity. Many variables. Also, not every part of Bangkok will be the same temp/humidity. This is a huge city. It tends to rain in different parts of the city, rarely raining everywhere at the same time. Heat and sun will dissipate humidity. Some parts of the city will get more sunshine than others. It is always warm here, though. :D
I agree on the airflow. I have computer fans in the pumidor to keep the air moving and usually open the door for a while once a week to get some fresh air in there.

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