I’m not really a shu expert — or even all that into the type compared to sheng — but I’ve drank a good bit of it (as is true of many other tea types). I recently commented on some issues in two discussions that fill in a lot about the type: About aging and storage issues, and factors that go into final experienced aspects in versions.
Someone in the Gong Fu Cha group had recently asked a question about shu:
I bought a ripe puerh tea cake, my very first one but now I don’t know if I am allowed to drink it right away or I have to let it age first?? Also, is it ok if i put it in a sealed bag, you know the one for foods and leave it in a dark place. I live in the UK so it is not too warm however there is a lot of humidity.
Moychay 2015 Menghai gong ting shu pu’er
My take is that you can definitely drink a shu pu’er whenever you want to, but some versions benefit from resting or airing out for a while, which varies by individual version. If it has a heavy petroleum, tar, or even fishy taste or smell – that kind of thing could fade over half a year to a year. Typically that would be more of a concern with a newer tea version, such as with a shu that was within two years or so of being produced. Not all versions pick up that sort of fermentation-processing-related character, so it just depends.
Humidity is probably not a concern; even up to around 70 % RH most likely the cake wouldn’t mold, and that is quite damp. More humid than that and it might.
It’s typical to not completely seal either sheng or shu pu’er, to not let them experience air exposure to the degree of sitting them out on a counter only enclosed by the paper wrapper, but also not sealed in a multi-layer type packaging used to keep other kinds of teas very isolated from air contact. Keeping it in a ziplock type bag is probably a reasonable option; those do “breathe” a little.
Letting the tea get cold and then warm again is a main problem: This will cause condensation on it. It’s hard to imagine what storage conditions would bring that up (putting it in a refrigerator and taking it back out?), but the idea of avoiding it actually getting wet is important. It would mold fast.
In the longer term that kind of tea will mellow and deepen in character some but it’s as well to just drink through it, unless it needs time to settle for some reason.
In another discussion some time ago someone mentioned moving from one apartment to another, and taking stored pu’er out of an air conditioned environment and into a much warmer setting. The tea molded, probably related to condensation caused by that change. High humidity is the main input that would cause mold, with some potential for air contact to limit that risk, but tea getting wet is worse yet.
There’s a lot more that could be said about optimum storage for sheng and shu, about humidity ranges that work best, airflow issues, or related to external contamination by other smells. A former blog post, also shared to TChing, covers a number of articles I’ve written on different aspects.
Comparing shu versions; different color might relate mostly to fermentation level
I wrote another summary of issues related to shu puer in a discussion thread in the Tea Forum:
So I’ve had enough shou that I am able to start noticing differences or at least preferences in teas. I found one I really like from Mandala, but other than knowing where it was harvested, Boulang, there isn’t a lot of write up on the storage and other factors that influence the tea… Trying to determine what factors about the tea make me appreciate it over others so I can look for other tea with similar characteristics.
To me shu kind of just tastes like shu, as uniform for different versions as any other tea type, but still I can add how I interpret a few main variables, since I’ve tried a bit.
Source region: I’ve not really drank enough to try to isolate inputs related to area, as is more commonly discussed for sheng. This comment is just to frame that context, that to me this can sort of get lost among other concerns, or might only show up after sorting past an awful lot of examples to isolate other inputs.
Fermentation level: This isn’t hard to pick up, so the opposite. I’ve wondered to what degree relatively lightly fermented shu might have more aging potential, but it takes a lot of exposure to piece together individual causes and effects, so I don’t know. The effect is what you would expect, highly fermented shu is much earthier, more prone to aspect range that might improve with some settling, and lightly fermented is much more subtle.
Whole leaf versus chopped material: Again what you’d expect, whole leaf is more subtle, less intense, probably a little cleaner in flavor aspect, and chopped material comes across as stronger, but not always in a good way. To me the difference related to this factor is more clearly tilted towards whole leaf being much more positive for sheng, because of how aspect range for both plays out. Shu that is made from relatively ground material tends to be bad though. I think some tuochas and mini-tuochas tend to be bad to awful in relation to a convention of those being lower quality, not related to there being any necessary connection.
Bud content: High bud level shu is often sweeter, lighter in tone, with a flavor that can even trail towards tasting like cocoa. A couple of references might help place that, a Yunnan Sourcing sampler that lets you click through to their take on grades, and a review I did of a version that seemed typical enough:
Customer Favorites “Loose Leaf Ripe” Pu-erh Tea Sampler – Yunnan Sourcing vendor link
Gong Ting shu pu’er mini-bar from Jip Eu – My own Tea in the Ancient World blog post
I’ve tried and reviewed better versions of high bud content shu than that before, but it’s probably a relatively typical above average quality example. If the idea here is to only be concerned with really good shu I’m not the person to be passing on any input; everything I tried was probably in the bad to upper medium quality range.
Later edit: For completeness it might help to reference comparison reviewing two better buds-heavy versions of shu from Moychay, a main Russian vendor, in this post (with the initial cake photo and brewed tea comparison photo from that).
Age: Odd to mention this so late in the list, isn’t it? To me shu doesn’t change all that much over time, compared to how many other people see that as critical, and making a lot of difference. I’ve tried a decent number of versions that were over a decade old (just not a decade earlier, then again after that aging), and they seem to just mellow out and deepen in character, and round off any rough edges. More issues come up with the tea needing some time to rest earlier in it’s life-cycle, most often within the first two years of being produced (or so). All of this is probably already familiar.
2017 huang pian (yellow leaf) Lao Man E shu pu’er version, from Moychay
Huang pian: I only mention this because I have a shu cake made from yellow leaves (huang pian material), and it’s really unusual, very mellow, but with a cool thick feel. I guess this is the opposite of the input related to high bud content. Having tried one version of this I have absolutely nothing to say related to generalities; it takes a number of examples to know how other version range probably goes, versus just trying a few.
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