Liu Miao shou mei white tea cake review, and on relative humidity

I just posted about buying a shou mei cake at a Bangkok pu'er themed shop, Teeta Talk (compressed white tea, nice they carry a range of products), and this is about trying it.  I've never owned or even tried compressed shou mei, aside from trying one in the process of buying this version.  It's a relatively standard tea type, so that comes down to my own inconsistent exposure to different teas more than the type being that rare.

That's going to keep happening; some tea type that seems relatively common will keep coming up for the first time, even though I do keep trying other basic teas and some from out of the way places, for some years now.  Since this is intended more as a "journey to tea" theme blog instead of expert opinion that'll work.

I found a bit on the tea online here; it's a Liumiao Tea product, with the following detail listed:

Name: Shou Mei white tea cake (public version) (2012)

Brand: six wonderful white tea
Item: BB300-006-2
Net content: 300g
Retail Price: 159.00 yuan  [converted, $23]
Product Origin: Ningde City, Fujian Province (Fuding)



The automatic translation of the additional description is cryptic, or even the brand name translated as "six wonderful white tea."  I had tried this version in the store instead and didn't like it nearly as well, but what do I know.

the origin, Ningde City, Fujian Province (Fuding), from Google Maps

Straight onto review then, even though there would be more to say about the type or source.  It's my impression that this is a typical commercial producer and product, both just don't turn up much in English language online search. Here's a reference to a different version by the same producer on Amazon that doesn't list the producer name at all; that kind of thing would make it harder to search for.

shou mei leaves, broken up (a little like autumn leaves)

The dry scent is nice, sweet and subtle, in the range of a sweeter forest floor scent.  I know different people would be using that term in different ways, and it would often mean something closer to peat, but I'm comparing the scent here to the clean, sweet, dry, earthy scent in autumn temperate climate forest.  It's a good thing, pretty far removed from the smell of peat or dirt.  It resembles dried hay, just sweeter.

The first infusion wasn't completely clear; in fact a bit cloudy.  It's been odd hearing people comment so much on the clarity of teas since actual cloudiness just never comes up, but it just did for this.  It made me think back to a research article on pu'er storage about those teas fermenting due to the presence of fungus and bacteria, and how toxins go along with that, so a rinse step is really preferable for shou and aged sheng (that research article, mentioned in this post on pu'er storage).  Here's some input from that:


An interesting finding is that the most sought-after tea, aged raw Pu-erh, has a fungal community more like ripened than young raw Pu-erh, and a similar trend was seen for the bacterial community (Fig 3)....  Multiple mycotoxins were detected from either or both categories of Pu-erh, but all but patulin and asperglaucide were under the safety limit. For safe drinking, we recommend discarding the first brew.

starting to open up, looking more like autumn leaves

Given all that background I still tasted that rinse--just a few drops worth--but dumped it, and gave it a second fast rinse.  The tea is five years old, stored in relatively damp climate, just less so and more temperature controlled in a store space.  I didn't notice cloudiness in the initial rinse when I tried the tea again later but I didn't drink it.


You might wonder, what difference would aging make, and how would that have varied stored in a dry place versus in Bangkok?  I can't say much about the first point, but I did write up some thoughts on humidity variation after this review.

Back to tea review (end of that tangent)

I went long on the second infusion, distracted by writing, so I can describe what a long steep is like.  It's nice, but still subtle.  There never will be even a hint of astringency from this tea.  That's not a surprise, really, but interesting to experience it.

The flavor range is still similar; light, earthy, and soft.  It does remind me of brewing a mild version of fall leaves.  There is sweetness to the tea but that's subdued as well.  It's not really complex, not floral, without much mineral, so just a bit subtle in overall effect.  Of course brewing it stronger, as I just did, can help offset that, but it only varies so much.

medium strength infusion

When I tasted the other version in the shop I just wasn't picking much up, which is why I didn't care for it.  The trace of range I did get was interesting, there was potential there, which is why I still bought this tea, a different but similar product.

The next infusion was shorter, but still around a minute, and it didn't lose much for intensity.  It's still subtle, and that's still a lot of infusion time compared to most tea types at the same brewing parameters (it is Gongfu style, a high proportion of tea to water, even given that style range).  A more typical 30 second steep just wouldn't bring enough flavor out, unless someone adapted to drinking this tea very lightly, which does seem possible.  Different tea types seem to work better at different infusion strengths (that's a given, isn't it?), and it's interesting how people tend to be divided about white teas related to that.  Some go with those long 5 to 7 minute Western style brewing times, and bump it up to a more typical strength range for other types, and others just go with the lighter presentation.  I might favor different strengths depending on the character type of a white tea.

fully opened, on the darker side

Even though this tea is quite subtle there is some complexity there, it's just all in a closely related range.  That dry leaf range is accompanied by some dried hay, supported by mild underlying tones like sunflower seed.  It might even pull a little into chrysanthemom / sunflower range, a bit of light, mild floral.  All that is still quite mild, and not unrelated in flavor range, so it doesn't come across as complex even though it expresses some complexity.


The flavors are clean enough, not murky at all.  That was part of my initial concern related to the cloudiness, along with potentially being poisoned, which completely resolved after the rinse.  All this isn't so far from that Sri Lanka Peony style tea awhile back (described in this post).  At first I wasn't attached to it but after drinking it awhile the complexity and that specific profile were really pleasant, and this also is, I'm just not quite there yet.  I could imagine someone being on a different page and not liking it.  It's probably a little less complex than that other tea, with less in the way of mineral undertones, and a bit less full feel, but the general range is pretty close.  It's not typically part of the scope of discussion in a tea blog but I paid a lot more for that Ceylon version than this one, on the order of a bit less than half as much for 1/6th the amount of tea (this is a 300 gram cake).  That tea was slightly better and this one a much better value, but the chance to see it evolve through aging draws it a little closer, and it might be the better tea in a few years.


It seems possible the woman in that tea shop had been using short infusion times appropriate for pu'er in brewing a different shou mei sample tasting, especially necessary for sheng, which caused that related tea to just not taste like much.  It's quite subtle related to other tea type results even brewed longer but a range of flavors are there.

the final test:  she liked it

I went long on another infusion again, a bit too spacey for controlled brewing this morning, so it's probably as well I'm on this particular tea.  Brewed strong it's still subtle but it picks up an unusual fullness.


In conclusion, the tea is nice.  It'll be interesting to see how it changes with aging, and it was inexpensive enough I won't mind sharing it (some).  Before closing this post I'm also going to ramble on about humidity, a factor related to tea aging (fermentation, assuming this is going to undergo that, not completely a given).  In particular I'll discuss how temperature range relates to relative humidity, which I never really will link to the comfort zone of the bacteria and fungus mentioned in that pu'er fermentation related citation.

On a storage environment issue, all about humidity

A bit of aside on local climate:  in the house in Bangkok where I live we experience the natural environment, which is hot and humid, except for using air conditioning when we sleep.  There is more detail on that humidity part here:






When you see people discuss humidity related to pu'er storage they tend to not pair that consistently with discussion of temperature range, and express it in relative humidity percentages.  That one measurement, RH, is convenient, easy to work with, just one number, and that number is meaningful.  The range I live in is typically 70% to low 80s here, per that graph, at least outside.


I'm not a weather expert, but I am an engineer, with a bit more background in lots of subjects as a result, so I'd like to pass on what the limitations are of that humidity specification.  I'll touch briefly on why there are some cases where people might move onto more specific discussion of the actual amount of water in the air.  To cite an unrelated example, data center humidity range guidelines--about facilities for IT equipment--aren't only specified in RH in the more recent forms, also with some reference to dew point values.  To be clear, if you specify the specific air temperature and relative humidity you have expressed how much water is present in that air, with slight variation related to local pressure, but you get the idea.

ASHRAE 2011 thermal guidelines for computing equipment environment range

The short version:  air holds more or less water at different temperatures, so saying that it's 70% relative humidity (RH) here in Bangkok now, when it's close to 90 F (32 C, how we measure temperatures in Thailand), and 90% RH somewhere else where it's 65 F (more like 18 C) relates to a lot less moisture in the cooler place.  The air just won't hold as much at lower temperatures, and RH is relating to the amount relative to what the air could hold.  All that's probably not interesting to most people, but the chart above spells it out in even more detail, along with some guidance on what IT equipment should experience.  That part is really complicated, with variation by type of equipment (shown in the different ranges), and all of it a little controversial.

Maybe it's of more interest to me than most, but it's particularly interesting what happens at the far extremes of temperature.  Around 0 C (32 F; everyone knows that) air can hold very little moisture, relative to at higher temperatures, so when you go out in the cold and it feels damp there is still not much water in the air.  That's also why when you mix cold outside air in the winter into your home it feels bone dry inside, because that outside air contains next to no humidity, and as a result the indoor relative humidity (RH) could drop to next to nothing.  Of course that's why static electricity effect increases.

To put numbers that that effect, on that psychometric chart air at 50% RH at 0 C / 32 F heated to 25 C / 77 F would then contain 10% RH, with no change in actual moisture level (water content, in this case 2 grams per kilogram dry air).  On the upper side from 90-100 F (32-37 C) air can hold loads of moisture.  That explains why when it's 32 C (90 F) and 80% RH here it feels oppressively hot and humid; evaporation of sweat to maintain body temperature stops working well.  At 25 C (77 F) at the same RH it's only a bit damp, and there is actually half as much water in the air.


It's interesting that the current weather reporting says the dewpoint is around 24 when the temperature is 26 (when I first started tasting this tea), and the "realfeel" is as if it were 35 (well into the 90s).  That seems to not really capture that effect, that it still feels cool--to people that live here--but quite damp.


I can only guess at how fungus and bacteria relate to the two differences taken together, if RH or absolute water amount is more critical to them, or if temperature also is for life cycle.  My guess is that they're durable little organisms that thrive across a broad range of conditions, but especially well where I am right now, when it's quite warm and damp.


Another reason to go into all that:  that shou mei cake may have been aging a good bit faster than if it were somewhere cooler and dryer.  It seems likely that most discussions of pu'er aging environment factors overemphasize humidity concerns due to oversimplifying temperature as a factor.  I don't know for sure that shou mei ages and ferments related to exactly the same micro-biological elements--fungus and bacteria--performing the same role, and that doesn't match part of the typical sheng back-story, but I expect that's the case.  It's one more subject to revisit later.