Ripe puer storage question

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May 16th 17 8:38 am
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Ripe puer storage question

by beanbag » May 16th 17 8:38 am

I remember reading a post here by somebody saying that they stored their puer in airtight bags, and they aged fine. Hojo Tea thinks so too. My question is given that I can maintain the humidity with a Boveda pack, what is the rational between storing with very little airspace (airtight bag) vs more freely flowing air (like a big jar with a slightly leaky lid)? What is the purpose of airspace or airflow? I'm sort of worried that the "aromatics" will go away if there is too much space for them to evaporate away. I mean, normally dry foods are stored with minimal airspace for this reason. I get that you want the initial fermentation stink to go away, but afterwards?

On the same hand, I don't think the little buggers (microbes) are gonna use up the oxygen if it is stored in a tight bag. And even if they did, so what?

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May 16th 17 9:47 am
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Re: Ripe puer storage question

by kuánglóng » May 16th 17 9:47 am

From how I see it the main purpose of airflow is to avoid a critical accumulation of moisture on the surface of compressed teas ('wet spots') - which above a certain threshold (also depending on the temperature) will inevitably lead to mold. The higher compressed your teas (cakes, tuos, bricks) are the longer it takes any additional moisture to reach the core and distribute evenly inside the compressed tea - most of any additional moisture will accumulate on the surface and can reach dangerous levels, resulting in mold.
I've done lots of comparative storage experiments with all sorts of tea over the years (pipe tobaccos before that) and have come to the conclusion that at the same storage temperatures any pu ages just as well in a multi-layer bag (no simple PE zip-locs! - different story) IF it has the right amount of moisture! (I keep most of my pus at about 8% relative moisture) and there's some little air left in the bag. To me the main 2 advantages of storing pu in multi-layer bags (solid impermeable aluminum barrier) are that
1. compared to more open storage solutions the loss of volatile components is vastly reduced, like you've already mentioned and ...
2. once you have established the right moisture content in a compressed tea and store it in a sealed ML-bag there's no need to constantly monitor your tea - it won't lose any of its moisture in there and can age in peace.

While this isn't the end all and be all of storage solutions and not for everyone - you need to exactly know what you're doing and be willing to take some measurements here and there, I'm perfectly happy with the results I got so far, haven't lost a single tea to mold ever but will also keep experimenting with other kinds of storage.

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May 16th 17 12:31 pm
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Re: Ripe puer storage question

by Psyck » May 16th 17 12:31 pm

What does 8% relative moisture mean? Is it the percentage weight of water in the tea cake to total weight of tea cake? How do you measure it?

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May 16th 17 3:29 pm
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Re: Ripe puer storage question

by kuánglóng » May 16th 17 3:29 pm

Psyck wrote: What does 8% relative moisture mean? Is it the percentage weight of water in the tea cake to total weight of tea cake?

Yes.
How do you measure it?
There are different ways to measure it but since I don't have any of those special instruments here I sacrifice a small sample of the tea (exactly 5.00g) and some aluminum foil (tare first), place it on a heat source (stove top, toaster, ...) until all the H2O has evaporated (be patient), weigh what's left and do the math - again, I've done that with pipe tobaccos for many years and never had any issues with mold. All you need is a couple minutes, a heat source and a cheap digital scale that lets you measure hundreths of a gram (couple bucks on eBay); those that I've bought over the years are more than precise enough for this kind of job.
I've seen some folks claiming that teas 'don't age' in bags and I wonder if any of them has done any comparative experiments themselves and/or have measured the exact relative moisture of their cakes - you can't expect a relatively dry cake, tuo or whatever with less than 5% relative moisture and kept in a simple PE ziploc bag to age as fast as the same cake in a pumidor, can you?

May 16th 17 4:38 pm
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Re: Ripe puer storage question

by beanbag » May 16th 17 4:38 pm

What I've started doing is to store the puer cake in a bag with a Boveda packet. Then I weigh the packet a few days later to see if it got lighter.

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May 17th 17 2:50 am
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Re: Ripe puer storage question

by john.b » May 17th 17 2:50 am

I researched this issue last year for a blog post. The basics have already been expressed here; there is a school of thought that holds that sealing pu'er for storage makes sense, versus the more typical acceptance that pu'er shouldn't be sealed. I don't really have personal opinion or experience to add to what I wrote; I just reviewed it and a little about what fermentation is since I was looking into it.

I should note that the main issue seemed to be fermentation related to sheng pu'er, not ripe pu'er / shou, and that really could be two completely different sets of concerns. Per research study and testing done related to the microbe activity of shou versus sheng--cited in that blog post--the two types of fermentation are comparable related to that activity, although surely not identical, but the transition of shou later over time is not as significant, the factor or additional fermentation activity.

To summarize one finding, there seemed to be a general trend for sealing to make sense--per that take--when the environment is too humid. Or that just could have emerged mainly from one opinion, with Hojo (a vendor) being the main source referred to as the advocate of the practice. Another potential factor driving that was the idea that limiting air contact is a good thing, something most agree on, with differences over what limits are and how to set limits.

Intuitively oxygen and moisture contact would both be required for fermentation, since microbes are playing a role in that (more on that in a reference source in that post), but it's conceivable that if a tea isn't sealed for years at a time limited air contact could refresh available oxygen sufficiently.

One standard take on storage related to humidity and fermentation, per my limited understanding, is that the natural cycle of humidity variation over time related to typical weather change is seen as a good thing. Again that probably relates more to sheng, and surely that's not an idea held by all. It seems possible that long term sealed storage may disrupt that effect. It doesn't really work well to think through how microbes might benefit from humidity variation using ordinary reason but who knows how well intuition captures the inputs to their own life experience.

At any rate these are just some ideas I turned up in reading that I passed on in this post, and more first-person experience from others here would surely be a helpful addition to that:

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

May 17th 17 4:32 am
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Re: Ripe puer storage question

by Muel » May 17th 17 4:32 am

john.b wrote: I researched this issue last year for a blog post. The basics have already been expressed here; there is a school of thought that holds that sealing pu'er for storage makes sense, versus the more typical acceptance that pu'er shouldn't be sealed. I don't really have personal opinion or experience to add to what I wrote; I just reviewed it and a little about what fermentation is since I was looking into it.

I should note that the main issue seemed to be fermentation related to sheng pu'er, not ripe pu'er / shou, and that really could be two completely different sets of concerns. Per research study and testing done related to the microbe activity of shou versus sheng--cited in that blog post--the two types of fermentation are comparable related to that activity, although surely not identical, but the transition of shou later over time is not as significant, the factor or additional fermentation activity.

To summarize one finding, there seemed to be a general trend for sealing to make sense--per that take--when the environment is too humid. Or that just could have emerged mainly from one opinion, with Hojo (a vendor) being the main source referred to as the advocate of the practice. Another potential factor driving that was the idea that limiting air contact is a good thing, something most agree on, with differences over what limits are and how to set limits.

Intuitively oxygen and moisture contact would both be required for fermentation, since microbes are playing a role in that (more on that in a reference source in that post), but it's conceivable that if a tea isn't sealed for years at a time limited air contact could refresh available oxygen sufficiently.

One standard take on storage related to humidity and fermentation, per my limited understanding, is that the natural cycle of humidity variation over time related to typical weather change is seen as a good thing. Again that probably relates more to sheng, and surely that's not an idea held by all. It seems possible that long term sealed storage may disrupt that effect. It doesn't really work well to think through how microbes might benefit from humidity variation using ordinary reason but who knows how well intuition captures the inputs to their own life experience.

At any rate these are just some ideas I turned up in reading that I passed on in this post, and more first-person experience from others here would surely be a helpful addition to that:

http://teaintheancientworld.blogspot.co ... ation.html
Hey John, that is a very good explanation :D :D :D. It is very similar to an article in Chinese I read years ago.

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May 17th 17 12:37 pm
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Re: Ripe puer storage question

by Psyck » May 17th 17 12:37 pm

Thanks for all the points made so far, useful info.

In my own case, I live in a temperate tropical zone that is pleasantly warm & humid all year round, so my whole house is a humidor & I'm not particularly worried about temperature or humidity but more on the other aspects of storage.

Why is it that ripe and raw are in general stored the same way? After all one is already aged and other needs to be aged, so shouldn't they be handled differently?

More specifically, why are they stored as cakes and not as maocha? Is it merely for convenience? I vaguely remember reading somewhere that sheng would age more 'gracefully' as a cake unlike the faster ageing as maocha - though I never understood why. However, at least in the case of shu storage, which is the topic of this post, would it not be preferable to store it loose? Not just what you intend to drink soon, but all your cakes - surely it would at the least get rid of the dui wei quicker.

Jun 3rd 17 10:00 am
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Re: Ripe puer storage question

by Cwyn » Jun 3rd 17 10:00 am

Most of the advice here is for raw, not ripe.

First, try and determine if the ripe you have is light, medium or heavy fermentation. Light/medium will have some greener tea leaves that show in the vessel after 7-8 steeps. Heavy fermentation has leaves that look almost black and don't change color with steeping.

Heavy fermentation teas are done. They will not ferment further, though with long age they will eventually peak and fade, but have an antique taste. They can be broken up and tinned to clear them faster.

Lighter fermentation teas have raw green pieces that will age slowly like sheng. This reduces the fade, and increases complexity because you have some newly aging tea in the mix. These teas need storage like sheng, but often a cloth bag suffices. If you just have a small collection, and plastic bags, just use them and don't worry too much.

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Jun 3rd 17 10:21 am
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Re: Ripe puer storage question

by jayinhk » Jun 3rd 17 10:21 am

I've never tried kuanglong's method of storage, but it would make for an interesting experiment for sure. :) Want to send me a sample of tea you've aged that way? I'll send you something back!

Shu is traditionally aged like sheng because that's what people in HK have done since the 70s; shu can absolutely age into something much nicer than when new and freshly pressed. I haven't tried many shu pu erh that are good in the first year after fermentation, but that kind of tea does exist and is really quite lovely.

I like to dry store shu so it develops sweetness, smoothness, and date-like flavors (I love shu like that). The best examples I've had of tea like that have been in HK and Taiwan. Now that I've figured out why it tastes so good (humid dry storage), I buy lots of shu to age.

Sheng obviously ages well and transforms, but so does shu! Aging has a huge effect on the quality of shu. Poor storage (too dry or too wet) will ruin both, but good storage drastically alters both in good ways.

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Re: Ripe puer storage question

by Psyck » Jun 3rd 17 12:08 pm

jayinhk wrote: I've never tried kuanglong's method of storage, but it would make for an interesting experiment for sure. :) ...
Isn't that one of the more common methods of storage? Several times when I order cakes, I receive them tightly sealed in plastic, completely air-tight. I always thought storing them completely sealed is a fairly regular practice both among vendors and consumers.
Edit: well he leaves a little air inside, but its is the same point - sealed vs open storage...

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Jun 3rd 17 12:20 pm
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Re: Ripe puer storage question

by jayinhk » Jun 3rd 17 12:20 pm

Psyck wrote:
jayinhk wrote: I've never tried kuanglong's method of storage, but it would make for an interesting experiment for sure. :) ...
Isn't that one of the more common methods of storage? Several times when I order cakes, I receive them tightly sealed in plastic, completely air-tight. I always thought storing them completely sealed is a fairly regular practice both among vendors and consumers.
Edit: well he leaves a little air inside, but its is the same point - sealed vs open storage...
It's common practice to seal in plastic to stop aging and odor exchange during shipping. I wrap cakes in Saran before shipping for this purpose. It is also done to stop aging and further decomposition down here in HK.

My dad lived in Austria and had some traditional storage sheng in a plastic jar. My mom and dad thought pu erh should be stored airtight. That stuff had HK humidity in it. After several years in the jar, it smelled and tasted like storage all over and even airing it out for years didn't help to get rid of the smell and taste. That tea was essentially ruined.

At a lower humidity level it might be ok, though, but it certainly isn't the method commonly used in this part of the world. Aged cakes are also wrapped to stop them from breaking into bits from handling.

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Re: Ripe puer storage question

by stevorama » Jun 3rd 17 2:52 pm

My friend was given a good and expensive aged sheng pu er years ago. She didn't know what to do with it. She put it into mason jars (glass canning jars.) It stayed there for 9 years unopened! We brewed it the other day. Possibly the best aged sheng I've ever had. I'm guessing the tea is from the 80s or earlier so plenty of time to age before going in the airtight jar. Also, the jar smelled a bit like pickles (it stored pickles before tea,) but the brewed tea didn't. :mrgreen:

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Jun 3rd 17 6:37 pm
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Re: Ripe puer storage question

by jayinhk » Jun 3rd 17 6:37 pm

stevorama wrote: My friend was given a good and expensive aged sheng pu er years ago. She didn't know what to do with it. She put it into mason jars (glass canning jars.) It stayed there for 9 years unopened! We brewed it the other day. Possibly the best aged sheng I've ever had. I'm guessing the tea is from the 80s or earlier so plenty of time to age before going in the airtight jar. Also, the jar smelled a bit like pickles (it stored pickles before tea,) but the brewed tea didn't. :mrgreen:
Down here, very old tea is also stored in glass jars. Again, to prevent deterioration. The key is to get the humidity level just right. I think with the right humidity percentage, tea will age. How it compares to tea that is allowed to breathe would make for an interesting comparison!

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Jun 3rd 17 7:19 pm
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Re: Ripe puer storage question

by stevorama » Jun 3rd 17 7:19 pm

jayinhk wrote: Down here, very old tea is also stored in glass jars. Again, to prevent deterioration. The key is to get the humidity level just right. I think with the right humidity percentage, tea will age. How it compares to tea that is allowed to breathe would make for an interesting comparison!
Perhaps she did the right thing then! Except for the old pickle jar part. And she put one jar in the refrigerator and one in a cabinet. I tasted the cabinet jar. I'm gifting her a ginger jar to use if she wants. :D