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I understand there is a need for the tea to get "accustomed" to your environment but what is the science behind that?

It is usually packed in plastic and put into a cold environment. Blocked off from air and subjected to temperature swings. Letting it warm up and have a bit of a humidity sauna will do a lot. Just as we need the time I think the tea needs the time to get back in swing as well.

No science but only dozens of experiments, the tea has always been really disappointing if brewed just upon arrival and much better if it rested for a few days/weeks.

I came to tea thinking that the whole "rest period" must be BS, until I ordered a few ~10yo factory cakes that were completely undrinkable on arrival. I'd thought them a complete loss, but after three weeks the obnoxious smokiness and a harshness I can't describe had receded, replaced by a sweetness that wasn't there before. This continued for about a month and a half and they've stayed steady since then. Fwiw I stored them at ~78F and 75%RH for that period.

I still don't accept the oft-repeated theory that "the microbes need to acclimate" - you're not tasting microbes, you're tasting years of accumulated metabolites and changes to the substrate, and a couple of weeks shouldn't affect that significantly as far as I can fathom.

That said, I can't ignore the night/day difference and I'f had similar (if less significant) experiences with other cakes, so I just accept it.

The only thing I can think of is that if teas are pulled from storage units which might not be the cleanest environment or might trap certain volatiles, that these volatiles might take a while to air out once the tea is removed from that environment. It's just a loose hypothesis, but it's the best I can come up with.

I like to use the analogy of 'cooking from frozen'. Generally, you should 'defrost' before cooking to get the best out of your product, it cooks properly and just tastes better overall. I think that something happens on many shipping routes, for example, airmail, with its particularly cold and low-pressure environment. It's also the same reason that the teas can taste noticeably different on different days as the weather changes.

I do believe it's related to the specific makeup of tea. However, I'm not well read on this, and I'm just another tea head with experience of drinking and sharing good Puer, and a bit of a foodie too. As for how long to 'rest/defrost' the tea... I believe the key factors are getting the tea into an 'ideal' storage condition before drinking. Personally, I think if the tea is in the correct environment (decent temp/RH), around 5-7 days should be enough. Picking the right days for samples is also something I try to do as there's nothing worse for me than trying to do a tasting session on a day with poor weather conditions.

Phil

It is the same for a lot of things, travel between different climate zones, different humidity and air pressure, etc. Add to that the artificial environment of an airplane, or worse the smells of a container ship and it makes a lot of sense to let it calm down.

Wood transported between continents has to be let rest for quite a while until it is acclimatised. Otherwise it will still move and deform when used to early. Why would tea be any different?

Most roasted tea need to rest before they are ready to be consumed.

Perhaps unrelated to your question, but there is also the oxidation thing. Some teas taste significantly better (smoother, sweeter, more aromatic...) after some period of a rest in a small closed jar, than how they taste when straight from the sealed bag or pried off a cake. This is a bit similar to letting a whisky/brandy/wine/... rest after pouring into a glass to allow it to open (also bottom half of the bottle tends to taste sweeter/smoother). There is this need to oxidate some of the aromatic compounds, but not too much.

I noticed that every sheng I tried was much stronger/bitter if I didn't let it rest before drinking it. Older sheng usually has a stronger storage taste at first so letting it rest is essential before judging it. Shou, especially relatively young shou tends to have a stronger wodui if I don't let it rest for at least a week or two first.

That doesn't stop me from tasting some of my teas immediately but I don't want to waste the samples (especially the more expensive ones) and I never give my final impressions before I've had it for a month.

Bok wrote: ↑

Wed Jan 03, 2018 7:20 am

Wood transported between continents has to be let rest for quite a while until it is acclimatised. Otherwise it will still move and deform when used to early. Why would tea be any different?

Because humidification of wood causes expansion, and physical size/tension/compression are very relevant properties of wood for most purposes, but hat is not true for tea.

When you saturate tea with boiling water, you don't care (directly) about how well-hydrated the tea leaves were to begin with. You aren't relying on tea to hold its shape, or to resonate at a specific frequency that is affected by tension.

To turn the question back around, why would tea have a need to reach a new equilibrium moisture content when moved to a new environment?

Atlas wrote: ↑

Wed Jan 03, 2018 6:02 pm

Bok wrote: ↑

Wed Jan 03, 2018 7:20 am

Wood transported between continents has to be let rest for quite a while until it is acclimatised. Otherwise it will still move and deform when used to early. Why would tea be any different?

Because humidification of wood causes expansion, and physical size/tension/compression are very relevant properties of wood for most purposes, but hat is not true for tea.

When you saturate tea with boiling water, you don't care (directly) about how well-hydrated the tea leaves were to begin with. You aren't relying on tea to hold its shape, or to resonate at a specific frequency that is affected by tension.

To turn the question back around, why would tea have a need to reach a new equilibrium moisture content when moved to a new environment?

You are right, and to connect to the previous poster, what is important for tea is oxidatisation, so my best guess it has to do with changing air quality. Maybe it is something that can be imagined like dust settling in water, after let to rest? Some sort of nanoparticles that get disturbed when tea travels over long distances?

Bok wrote: ↑

Wed Jan 03, 2018 6:50 pm

You are right, and to connect to the previous poster, what is important for tea is oxidatisation, so my best guess it has to do with changing air quality. Maybe it is something that can be imagined like dust settling in water, after let to rest? Some sort of nanoparticles that get disturbed when tea travels over long distances?

Not to say that oxidation isn't important (and I know little of how oxidation affects pu'erh), but it cannot be a relevant concern here either; oxidation is a process that occurs over time, and the two weeks or few months a cake spends in shipping or resting at home is eclipsed by the (often) years a cake has sat in storage.

With all due respect, saying that the change may be due to "settling of nanoparticles" or somesuch is comparable to saying "it might be because of faerie magic". If one has to reach that far for an explanation, the most truthful answer is "I have absolutely no idea", which is fine - this isn't a phenomenon that has been properly researched yet, as far as I'm aware.

Kupuntu wrote: ↑

Wed Jan 03, 2018 2:49 pm

I noticed that every sheng I tried was much stronger/bitter if I didn't let it rest before drinking it. Older sheng usually has a stronger storage taste at first so letting it rest is essential before judging it. Shou, especially relatively young shou tends to have a stronger wodui if I don't let it rest for at least a week or two first.

This is what makes me wonder how much of the phenomenon is simply due to dissipation of storage-related volatiles.

Has anyone ever weighed in with (for example) how single cakes and samples purchased from other individuals have developed over the first few months of ownership? That would yield a fair idea of whether it's only stuff that just got pulled out of a warehouse/tong that has a problem, or whether it's something that happens any time you throw tea in a truck/plane for a week or two.

mrmopu wrote: ↑

Tue Jan 02, 2018 7:44 pm

It is usually packed in plastic and put into a cold environment. Blocked off from air and subjected to temperature swings.

Easy enough to test - I'll chuck a sample-bag in the fridge and come back to it in a couple of weeks. I'll swap another between fridge and (30degC) pumidor every second day, too. I'd be interested to hear what someone who was actually an experienced tea-drinker thought, though (hint hint ).

Even an experienced tea drinker is not necessarily a scientist, which is the only person who can answer this. Hint hint.

A lot of very experienced tea drinkers here in Taiwan often have some or other theories on a lot of tea topic which are more often based on Chinese whisper kind of knowledge rather than scientific evidence.

Bok wrote: ↑

Wed Jan 03, 2018 9:22 pm

Even an experienced tea drinker is not necessarily a scientist, which is the only person who can answer this. Hint hint.

To be clear, I was suggesting maybe Mopar could do the same, since his palate for tea is doubtlessly a lot more refined than mine and he might have a better grasp on whether there were significant changes outside of what might be expected from brew to brew.

As to the other bit, anyone who performs scientific enquiry can try to advance their understanding a little - being a professional (what I assume you mean by "scientist") just gives a better guarantee that you're doing it right. The correctness and rigour of your work determines how "scientific" it is, and amateurs aren't precluded from contributing to a body of knowledge.

It doesn't take a degree to try and isolate a potential variable.

Atlas wrote: ↑

Wed Jan 03, 2018 9:37 pm

Bok wrote: ↑

Wed Jan 03, 2018 9:22 pm

Even an experienced tea drinker is not necessarily a scientist, which is the only person who can answer this. Hint hint.

To be clear, I was suggesting maybe Mopar could do the same, since his palate for tea is doubtlessly a lot more refined than mine and he might have a better grasp on whether there were significant changes outside of what might be expected from brew to brew.

As to the other bit, anyone who performs scientific enquiry can try to advance their understanding a little - being a professional (what I assume you mean by "scientist") just gives a better guarantee that you're doing it right. The correctness and rigour of your work determines how "scientific" it is, and amateurs aren't precluded from contributing to a body of knowledge.

It doesn't take a degree to try and isolate a potential variable.

I believe I can do this. I have some stuff due Saturday or Monday if it tracks correctly. I think I can isolate a bit of one in the fridge and then one to acclimate. Refined palate, no no no just a simple tea drinker

Most of you folks must have very efficient customs and postal services if you are receiving your teas very soon after they have been in a plane. My shipments usually lie for several days and weeks in the warm and humid customs and postal offices of my city before reaching me.

Resting a puerh for a couple of weeks was among the first things that I heard when learning about puerh, and it made no sense to me. With completely sealed up teas, the only relevant external factor appears to be temperature, and I could not understand why that would make any difference.

I have never bothered to consciously compare the same puerh drunk immediately after delivery and after resting it for a few weeks, but as I recall, the few times I have done it, there was no noticeable difference.

Having said all that, puerh keeps changing over time, and this effect may not be something that could be easily proven or demonstrated - so I personally see no harm in letting tea ‘rest’ after its travel and slowly ‘awaken’ in your local storage environment before consumption - as least for those that you intend serious comparisons & tasting notes.