Wednesday, August 30, 2017

Fluoride in tea; a summary version

Originally posted as:

I recently researched the risks of fluoride in tea for a blog post, after a group discussion raised the issue.  To be clear, the probable risk is low.  I'll return to special cases where there might be real risks after filling in some basics.

Editor's note:  that earlier article went through more related to possible health risks, factors relating to fluoride levels in tea, particularly related to the age of leaves used (bud and first two leaves versus "lower" leaves, which are higher in fluoride content), and calculations related to assessing intake.  This article version is a shorter summary.

Fluoride is a positive dietary input found in tea, recognized as helping prevent teeth decay, and cited as one form of treatment for osteoporosis (a WebMD reference to that, and some general background).  But any dietary or supplementary inputs are beneficial or harmful within a limited range, and the focus here is on risks related to too much.

Basics related to Fluoride intake

-The earlier EPA recognized limit for fluoride daily intake was 10 mg / day.

-That was revised  to .08 mg fluoride / kg (body weight) / day.  Since I weigh 70 kilograms (155 pounds) 5.6 mg / day of fluoride is the long term limit.

See an EPA Questions and Answers on Fluoride reference and FLUORIDE IN DRINKING WATER: A Scientific Review of EPA’s Standards for more background.

-The treatment level of fluoride (added to municipal water) is .7 to 1.2 mg / liter (or ppm, parts per million; they work out to mean the same thing).

-Since fluoride occurs naturally in some water sources (wells or springs; it is just another mineral) the EPA sets a limit for a maximum.  They now recommend municipal water sources should contain no more than 2 mg / liter (a revised guideline), with a mandatory regulated limit of 4 mg / liter.

-Some natural water sources can contain over 10 mg / liter, although that is relatively rare.

Naturally occurring fluoride levels chart, places over 1.5 mg/liter supplement levels (source credit)

Fluoride in tea

 An Indian research paper provides a great starting point for amounts of fluoride in brewed teas:

That amount varies from 1 mg / liter up to around 3.5 mg / liter.

This table shows amounts of fluoride in different Chinese teas measured as amounts in milligrams per kilogram of dry tea (from "Fluoride Content in Tea and Its Relationship With Tea Quality"):

A bit of interpretation is required.  I do a lot more with the numbers and calculations in that earlier post but we can estimate brewed tea amounts from this, after some assumptions:

-50 to 100 mg fluoride / kg of tea are considered as low and high levels

-each cup of brewed tea is based on two grams of dry tea (not a given, but making 2 cups of tea using 4 grams of dry tea is within the standard range).  Essentially complete extraction is assumed here, not really a given in actual practice.

50 mg / kg tea * 2 gm of tea per cup * 1 kg of dry tea / 1000 grams =

.1 mg / cup of tea (or .2, based on the "100" value; up to .4, based on the very highest "200" range)

Sounds like not much.  Even if those are 6 ounce cups of tea it still only works out to 1.1 mg / liter on that higher "100 mg / kg" calculation (for over five cups of tea):

This estimation matches the Indian study relatively well (1-3.5 mg / liter of tea), with a range up to 2.2 mg / liter using that highest "200" value instead.

Additional thoughts / conclusions

Based only on the amount of fluoride in water there is almost no risk.  Drinking two liters of water a day treated to 1.2 mg / liter (the highest treatment level) adds up to 2.4 mg; well below either limit of 5 or 10 mg / day.  The recommended EPA city water maximum limit of 2 mg / day brings that to 4 mg / day (and the mandatory treatment level to double that, giving alarmists something to talk about, since that is a bit high).

Based only on normal consumption of relatively high amounts of tea (two liters per day) there is very little risk.  Even at the very highest level those totals don't exceed 7 mg / day, for the Indian study values, or 4.4 mg / day for the highest Chinese version.  But then averaging drinking two liters of tea per day really is a lot; that's a bit over eight 8-ounce cups of tea.

The obvious case when there could be some limited risk:  when both add up.  Preparing two liters of tea per day from fluoride treated water really could relate to an intake of 2.4 + 4-7 mg / day, on the highest side a good bit above the maximum long term intake for someone of my weight (5.6 mg / day), approaching the older recognized limit of 10 mg / day.

Other special cases:  high levels in natural water sources, or due to a recreational runner or construction worker drinking a lot of treated water.

more results from the earlier Chinese leaves study

Per online discussion there could be much higher risk related to some types of hei cha.  Those Indian study results seems to match that, with better teas relatively low in levels (more often based on two leaves and a bud plucking), with CTC teas made from other leaves.  Based on that other research there is potential for much higher fluoride levels for teas made using more of the oldest leaves.

My personal conclusion:  there is nothing to worry about, beyond those few special cases.

Editing note:  in reviewing a related issue I ran across the following reference for measured amounts in different teas, in the paper Assessment of fluoride concentration and daily intake by
human from tea and herbal infusions:

Some thoughts / interpretation:

-this matches the Indian tea study, with the general range of results of significantly under 1 mg / liter (starting at 1 mg / liter in that study, with the lowest range here roughly half that) up to over 3 mg / liter in some cases.

-a five or ten minute infusion time would match ordinary brewing practices; using a 30 minute brewing time is not typical.  For cases of cold brewing or brewing "grandpa style" (allowing tea to remain in contact with water) this higher level of fluoride extraction may result.

-lowest amounts are for buds-only or bud related teas, as expected (see the earlier related post).

-I hoped to review hei cha levels but they aren't included, except for pu'er, with those teas sampled all relatively low in fluoride level (.57 to 1.04 mg / liter based on 10 minute infusion time).

-oddly "Lipton" tea measured the second highest recorded level, and "Tetley Earl Grey" the third, after one outlier, Ygara Asta black tea.  Those Lipton and Tetley values are around the highest range for the Indian study (around 3 mg / liter), with the Ygara Astra in the range of double that (all varying by infusion time).

Monday, August 28, 2017

Rou Gui from Wuyi Origin (from Cindy)

Cindy sells more than one type of Rou Gui on her website (fruit, flowery, and cinnamon; I just looked), and I'm not sure which one this is, so it will be a blind tasting of sorts.

Rou Gui translates as cinnamon, of course, but they don't all have that characteristic taste (the Wuyishan area roasted oolongs based on that plant type, to be more specific).  When they do, per my prior experience, it's not typically exactly like the spice-jar version, a little darker and earthier instead.  I just reviewed two of them in this post, one from a local shop source, and only one of them was a lot like that.  But then bark from different plants is called "cinnamon," a subject I've passed across before, and touched on in that post.  On to review then, keeping it simple for once.


The tea scent is heavy on toffee, or maybe a dark caramel.  I couldn't really pick out fruit versus cinnamon beyond that.  The initial infusion was fast, a bit of a long rinse, typical of how I usually prepare such teas, not using a discarded rinse and not really try to get full infusion strength out of it the first go.

Based on first impression this is the cinnamon one.  It tastes a good bit more like cinnamon than I've noticed in her Rou Gui before, and I wouldn't say there is no fruit aspect to it but it's subdued in comparison.  The level of roast seems somewhat medium, not charred at all, but not necessarily light.  It's hard to notice that level without thinking about it, probably a good sign, that the flavors all integrate well.

This is a really nice tea; typical for what they make.  The sweetness, balance, the way it integrates, feel; it's all good, a well made tea.  It'll be easier to break it down based on a typical strength infusion though.  The second infusion will still be on the light side compared to how I would prepare some other tea types but in a more conventional range.

The cinnamon is stronger in the next infusion; no need to check with Cindy about which this is.  That one from my favorite local shop, Jip Eu, was roasted more and that really shifted the balance, slightly into the range of light "char."  It was still good tea, still decently balanced, but this is quite different for the roast level completely integrating with the character of the tea.  Again this doesn't taste like a spice-rack cinnamon.  It overlaps quite a bit with that flavor range, but it's a bit like other tree-bark spices taste too, more rich and less sweet, "darker," if that makes any sense.

And that's basically what's going on with the tea; it doesn't change all that much over the next couple of infusions, and keeps going well after those.  I could go on about feel (it's a little thick, and it seems to coat your mouth, it's nice), or aftertaste (it stays with you after drinking the tea, quite strong for half a minute, then trailing on for awhile).

With that cinnamon taking up so much of the flavor range it's almost a stretch to describe supporting aspects that join it in detail.  It's a bit complex, not really one dimensional, but that one narrow flavor range is most pronounced.  It's a good version of a typical style Rou Gui.  It might have seemed odd saying so much about fruit in the other reviews (citrus, often), but apparently that style is also available now, it's just not this version.

It seems strange to leave it at that, since so far I can sum up this review in one word:  cinnamon.  It's not like the version that goes into a cinnamon roll, so not quite that simple, but this is quite the opposite of a flavors-list review.  Sometimes the range of taste can seem narrow but not necessarily limited or simple, supported by an underlying warmer floral tone or light malt aspect.  I see malt as coming in a range of forms, although maybe not everyone is using the concept that way, as the edgy, pronounced malt in Assams that is usually coupled with astringency, or as the sweet, cocoa-like malt in Ovaltine, or as a related warm and rich but softer malted barley flavor range, more of a grain-like sweetness.  This supporting flavor range is closest to the last.

For people that are looking for subtlety or complexity in tea tastes it may not suit their preference.  For someone that loves that one aspect, looking for a Rou Gui that tastes like cinnamon, it could be ideal.  I really like fruit aspects in black tea or roasted oolongs so their version that's fruitier suits my individual preference better, but at some level that's what it comes down to, what someone happens to like.  This tea is clearly a higher quality version than the other two I reviewed in the other post I mentioned, it's just not complex in terms of expressing a lot of separate flavors range.

Two other factors could come into play, related to me as a reviewer, not the tea.  I've only tried this tea once, and I wasn't in a loud environment when tasting (for once; the two noise-makers were out), but I was feeling a bit tired, tasting it in the morning.  Not just noise or other interference but also disposition effects how we experience a tea.  I could probably expand on this description a little after a couple more tastings.  But I think this does capture the essence of it:  the tea is clean, a bit sweet, well-balanced, with integrated flavors, simple in the sense of not presenting a long flavors list, but complex in the sense of having dimensions to its character.  It's medium in roast level so that you can't notice that level without thinking about it, striking a balance that works well, and it tastes like cinnamon.

Sharing pictures (a completely unrelated tangent)

The pictures I share here are typically just my kids (beyond those of tea, or travel), but I wanted to pass on a slice-of-life set that describes my experiences here.  These are a few of the newest local park in Bangkok, the Chulalongkorn University 100 year anniversary park.  

For those of you into parks, for whatever reason, here is the main page of information about it, and another talking about green spaces in Bangkok and what the design is doing to conserve water.  A friend is a sustainable landscape design professor, and I took some landscape architecture classes way back when, so some of that seems interesting to me, but I'm mostly visiting parks to check out the kids' play areas.

not really at the park

Saturday, August 26, 2017

2007 Xiang Yi "Hei Cha Zhuan" Hunan Brick Tea

cool looking tea

I'm reviewing the third tea from an order of a few kinds of hei cha (from Yunnan Sourcing), part of a long awaited step to explore the type further.  So far I've covered a shou pu'er and Liu Bao in an earlier post, and now I'm onto a Hunan Brick version.  I'm excited to pass on results, even though I'm only started on the tasting, but I wanted to mention a post-script related to the last tasting first.

that order; modest priced versions, but interesting so far

That shou was nice (with full names for both above).  Others have been reviewing and discussing it online and it's quite well received, complex, with a good range of aspects, full flavored and pleasant, with no negative aspects (no mustiness, off flavors, tar, or petroleum, definitely no fishiness).  It might not pass for a much higher end tea due to the complexity and aspects range only extending so far but it's nice, if considering value as a main factor perhaps even exceptional.

The Liu Bao I found to be a bit musty, although I still liked it.  That's the part I really wanted to talk about here, that per later input others suggested that with some airing out that may subside.  I don't mean the week or two of rest teas are recommended to undergo after shipping, a settling in, the idea is to store it well away from other things with strong scents in a paper bag for half a year to a year.

Really it's hard for me to put it on a scale just how musty the tea was, as wetter stored versions go, since I just don't have much experience with that.  To some others that element might seem really mild, or maybe it could seem like the tea couldn't really completely come back from it instead.  I still liked the tea, it was interesting, but it might well be a good bit better in a few months to a year.  It's probably as well we're moving through the end of the rainy season here so the oppressive humidity will ease up in another two months, to help it air out.

Or after checking out an annual humidity graph for Bangkok maybe not.  I could swear the steam-room level of humidity I'm experiencing right now eases up, more than the bump down from over 80% to over 70% as shown there.  At least that tea won't dry out too much.  I'll check back on how that goes.

what the chunks look like

The Hunnan Brick tea review

The first look and smell of the tea was exactly what I'd been expecting for other types of hei cha; rich, sweet, a little earthy, and complex.  The scent reminded me of figs and stored hay bales, or a lot like an old canvas Army tent my parents used to have.  It weighed a ton, and stayed a little musty from seemingly never completely drying out, but it had a really cool smell.  I guess it smelled like figs and stored hay bales.

Thinking back that tent may have been from the Korean war era, since it was around in the late 70s (I'm a bit old myself since I was too), and it probably wasn't even new to my parents then.  It's conceivable that it could've been really old instead, but my guess would be that it was a 60's era tent (so post-Korean conflict, pre-Vietnam ramp-up).  They don't make them like that any more, and they shouldn't; that thing was heavy, and beyond that smell being cool it was probably a little like hanging out in the stacks in a library basement.

The appearance is what I'd have expected too: well-compressed chunks of a dark tea.  It looks and smells a little like that compressed Yunnan black tea brick I reviewed and bought awhile back, now that I think of it.

The first rinse was a bit light so I'll start in on the first real infusion.  It is a lot like that black tea brick.  The taste range from the scent is there, figs, an old version of dried hay, not really dry, light bright tones but earthier and sweeter range, with some depth to it.  It's clean in effect, not off in any way.  That part of the range sort of reminds me of the Yunnan compressed black tea but it's the underlying tone that really does.  It includes layers of molasses earthiness and sweetness with an unusual mineral tone, like the scent of an artesian well that draws up minerals from deep in the ground.  I really like that part, although I suppose that maybe not everyone would.  It's not off in any way, not difficult to appreciate, but it is different.

one version of an artesian well; this one is for local deer to get a drink

It's complex enough that different reviewers might fill in different 8 or 10 aspect descriptions for it.  I'm going with fig, older hay bale, mineral, and molasses as a start but really I think cocoa sort of works, and there's another dried fruit element that's quite pronounced, with fig not quite capturing that range.  I'd meant to check the Yunnan Sourcing description but hadn't yet; lets try that:

This is from the Xiang Yi Tea Factory in An Hua county of Hunan Province.  Xiang Yi is the second oldest producer of Hunan Hei Cha after Bai Sha Xi Tea Factory.

Hei Cha Zhuan (lit. Black Tea Brick) is composed of An Hua grown tea that's been picked and processed with frying, rolling, wilting and then sun-dried.  The bricks are tightly compressed which allows for slow but determined post fermentation. These are unique from Fu Bricks in that the golden flower spores are not introduced into the tea and as such don't exist.

This particular brick was stored in An Hua County of Hunan from 2007 until June 2016.  The smell of the dry leaf is that of dried fruit... very sweet and dense fruitiness happening.  The brewed tea is sweet and thick with (not surprisingly) strong fruit sweetness (think dried plums).  Tea can be infused 7 to 10 times if brewed gong fu style.  We recommend loosening the tea using a pick into smallish chunks layer by layer.  We also recommend using a clay pot and the hottest water possible.

I meant to edit that but it's all too interesting.  Unless I'm remembering wrong that compressed black tea was sun-dried, but surely the processing was completely different beyond that.

Kind of strange to be passing on background description during a review, instead of before or after, but I checked the Steepster reviews--it came up looking for this product page--and they were all pretty consistent.  Everyone liked it, and the different descriptions match well this time (maybe they cheated, and copied).  People only saw a lack of complexity as a possible drawback, but everyone reviewing it seemed to want to own some.  A couple of reviews mentioned an umeboshi flavor aspect, a Japanese salt plum, per Wikipedia more closely related to an apricot.  I'm not sure about that; I try strange Asian foods more often than most but don't keep track of them all.

Related to their take on aspects "plum" is the consensus for that fruitiness (that I'd left at fig and some other dried fruit), with sourness and wood also mentioned.  I suppose there is a bit of sourness, which would come across completely differently without that sweetness, fruit, and earthiness filling in the rest.  It's just a short step towards how dried plums come across, but absolutely nothing like the final effect in the Chinatown version that you get, that really intense sweetened and flavored version.

that Teasenz shai hong compressed black

It would be interesting to comparison taste this with that Yunnan compressed black tea, and to a limited extent I am comparing to the memory of it.  On the next infusion the sourness does pick up; I think that's actually common to both but a little more pronounced in this.  All those reviews really do capture the main flavor elements going on, with that fruit range (plum, etc.) and the lighter earthy tones (bark, aging hay bale) as the main experience.

Under all that though there is an interesting context tone for the flavor, that mineral range, which I'm describing as the scent of an artesian well.  If you pulled that out the experience wouldn't hang together in the interesting way that it does, and to me it's interesting on its own for being novel.  Or maybe I just like that smell.

Forgive another flashback:  when I was a child my grandparents, the set I saw less often, my mother's parents, had an artesian well flowing right in front of their house, piped up in such a way you could kneel down on a steel grate and drink constantly flowing water pouring out of a metal pipe.  The idea is that somehow underground pressure forces water to flow without pumping, like a natural spring, just related to the pipe running down into the ground instead.  Similar pipes sticking out of the side of a hill were kind of common back there.  In this case they used that as a water source.  You could stop and get a drink on the way past it, and every time we visited that's exactly the first thing I would do, and every other time my path naturally crossed by it.  That mineral smell is unforgettable, and that water was delicious, sweet and full of flavor.

Looking around online related to that well I tested how this tea does brewed for five minutes instead of more on the order of half a minute to 45 seconds.  An optimum infusion time would really vary by proportion used and personal preference, with water temperature and all the rest factoring in.  It's still fine; not better for being overbrewed, but the tea takes it well.  It's a good chance to get a look at what's going on in the tea from a different perspective, like the idea of using a bit of an oversteep (one standard, long brew time) to help identify flaws in standard tea tasting.

The idea of the earthiness being bark or dark wood really comes across brewed strong.  The feel thickens a good bit, and the aftertaste is really pronounced.  It's actually kind of nice, that mineral range, the sweetness, the sourness and fruit offsetting each other, with a rich sweetness and the mineral stronger in the aftertaste version.  I would prefer this tea brewed medium to slightly stronger, not exactly like this infusion, but the flavors and general balance work well at any intensity, so it might as well be a little stronger than average.  I tend to go the other way with most darker roasted oolongs, with lighter being better, and in the middle with most black tea types, not preferring them especially strong or light.

As I see it this tea would work well with different kinds of foods.  Drinking it alone would be fine, as some sort of afternoon tea, but that range could work well as a counter for something completely  different in taste, lighter in scale, maybe like a dried pineapple danish.  My thinking is that it's not so subtle that it's a strain to "get it," and the interesting way that complexity crosses your palate could be emphasized further by tasking you mouth to switch back and forth between two different ranges of flavors.  It would also help stop the effect of mild sourness from building up.

On the subject of "meditative space" that came up in the last review this time this house is quiet as a tomb, except for the odd tropical bird piping up, perfect for tasting.  My wife took the little noisemakers to a Chinese class (Mandarin) and a pre-school sort of event for my daughter.  She's three years old but just switched to her second school, from a Chinese-Thai local version to a British international school, but it still works out to have her do a weekend two hour social outing back there while my son does a language lesson.  I suppose that's intended as an explanation for why this rambles even more than is typical, venturing across online review and into what to snack on while tasting the tea.

more trouble than she looks to be in the pictures

Perhaps partly because I don't get this kind of quiet time often it's nice mostly drinking teas that aren't very challenging.  An example will clarify what I mean:  another review I've been meaning to get to is comparing two more of Cindy's teas (Wuyi Origin Wuyi Yancha oolongs).  I love those teas, and they're surely fantastic, two of the better teas I will have ever tried, but for those I would do well to spend an hour and a half mostly focused on the tea instead.  Tasting just one cuts back the scale of the task, and makes it easier, and I might finish most of that tasting and note-taking in under an hour.  For trying this tea alone, the Hunan brick, I'm free to mess around a little, to focus in and then check on something else.  I just passed on a lead on a Nepal tea contact while I was writing this.

Trying the tea again lighter works a little better, but in the middle towards the stronger side is how I like it.  It doesn't seem to transition much anyway; not like I'm missing something there.  In a couple of limited senses the complexity is limited but I like the tea; the aspects are nice.  It brews a lot of consistent infusions.  I've lost count of them, but aside from needing longer times to keep the intensity up the tea is still going.  I think some of the range has narrowed and the feel might be thinning but otherwise it's similar to the earlier version.  It moves a little towards metallic from mineral and thins as even more infusions pass but otherwise just keeps going.

I don't think this is the kind of tea I'll experience more and more from as I experiment with brewing adjustments but I will enjoy trying it lots more times.

This part is probably going to sound a little crazy but someone just asked for recommendations for a tea to try mixed with ice cream (I warned you) and this might work.  I recommended making up a version of Thai iced tea instead, trying to get that spicing blend to balance.  That would be especially suitable since it's like cooking; you could keep adjusting spicing to make it work well with the ice cream (only vanilla, I think; it would be uncivilized to try any other flavor with it).  But this tea or that Yunnan black brick might work too, brewed really thick.  A more obvious answer would be to go with a malty Assam, I guess, or a chocolatey Yunnan Dian Hong (more standard black), but I think the range of those two brick teas might also work well.

Wednesday, August 23, 2017

Tea as the hottest latest trend in Bangkok

This really is about tea as a local trend, and food trends in general.  A local tea acquaintance, the owner of the Seven Suns cafe, mentioned hosting a booth at a Matcha Mania event in the Paragon mall, arguably one of the two main malls in Bangkok.  I checked it out and it was well received; crowded, even.

lines at Matcha Mania

Matcha booths and shops are everywhere, edging into bubble tea's market share.  I'm not sure how an event theme really could ramp up the "mania" much but it did seem to.  I might have tried a Seven Suns matcha drink there but I did so not that long ago (which I wrote about here) and I wasn't into waiting in line.  I've been considering trying out hojicha soft serve for a very long time--it's around--but didn't finally get to that either.

menu board at the next booth over; it looked ok

that sausage (with a recipe for it here)

I didn't try any tea at all.  I'm not all that into matcha, except in ice cream, and eating a desert item right before dinner made no sense.  I had walked by a nice looking Northern Thai herb-spiced sausage on the way and bought some of that for dinner on the way out, along with sticky rice.

Other tea and food trends

I'm not a "trend" person.  I'm from a small town in North Western Pennsylvania, where time doesn't bother to cause changes in the normal sense.  I like it that I live in a part of Bangkok where the decades passing also doesn't change things much.  I wear plain clothes and drink plain, hot, traditional teas.  I suppose if one looks at the longest term some of those teas aren't traditional, since the story is that shou was invented in the 70s, and I drink a little of them, and I like tea style variations from places like Vietnam and Indonesia that probably didn't exist a decade or two ago.  But the general point is the same.

Related to transitions back in the States I feel like I might somehow completely become a stranger in my own country at some point, but visiting once in awhile helps offset that.  My wife and I moved to Bangkok from Honolulu a decade ago so that's plenty of time frame for changes to happen.  I was just back in PA over the Christmas holidays, and in Washington, DC, and NYC, with a very short stop in State College, where I first went to school (PSU).  All of those places probably lag a little compared to the West coast for transition pace but it was comforting to see it all about the same as I remembered.  Except NYC; I've only been there a few times, so it's not as familiar.

An online contact just mentioned a "cheese tea" trend that apparently became popular in China way back in May, mixing cream cheese into tea as a beverage, topped with a bit of sugar, salt, or some spicing to give it a twist.  I just saw a notice that I can get it here, but I'd be ok with never following up on that.  Oddly that online contact lives in Poland, and she cited a Polish tea vendor's Youtube video about how to make it yourself, I guess all typical of the world getting smaller.

at that mall; not exactly the same thing

As I was wandering that mall looking for that tea event a friend back in the US asked me by message if I'd tried a lighter form of Japanese cheesecake that is popular now, and my initial reaction was "of course not."  Then I remembered that my wife's cousin's wife is a baker, and she gave us a type of cake I wasn't familiar with over the weekend, so apparently I'd already been eating it for breakfast this week (Japanese cotton cheesecake, per her description).  It was nice.  There is more of running theme here than there might seem.

There is an emphasis on things being trendy in Bangkok.  I suppose it varies by where you go, and Paragon mall is a main place for that sort of thing.  That name seems to mean "exemplar" as much in the sense of exemplifying trends than relating to being an ideal mall.  I suppose it's nice though, to the extent that any is different from the others.

One local magazine covers updating preference shifts as well as any, BK Magazine, as in this post about 7 terrific Bangkok tea houses that are very serious about their cha.  Cha is Thai for tea too, for what that's worth.  The first three they mention are worth a look, which includes Seven Suns.  The two others I'm approving of are the old Chinatown cafe (Double Dogs), and the last a good place to spend $20 for small pot of tea, Peace Oriental.  I visited there once a couple of years ago, and it was ok, but I don't plan to ever go there again.

It's drifting off theme a bit but I'm in a FB foodies group here, even though I'm definitely not a foodie.  I cook; I guess that could count as partial credit.  They discuss restaurants more than novel food items, split between considering higher end places and debating who has the best burgers, pizza, Mexican, etc.  All the Mexican food I've tried here was somewhere between mediocre and awful but it would help to be a foodie, to visit restaurants a few times a week and explore further than I do.

The mall visit got me thinking more about trends, and that cheesecake.  Some looking around turned up ricotta cheese pancakes, and a Japanese tart version of cheesecake, and a place selling a hojicha flavored version of shaved ice.  Shaved ice is popular now, not the version from Hawaii, the fruit syrup flavored range, but the variation from Taiwan instead, more focused on fruit integration and use of condensed milk and other sauces.

It's not the same thing at all but I finally saw an I-Hop here, Thailand's first.  That's right, an International House of Pancakes (which I don't think was really all that international in the past).  It's strange to be mentioning low end breakfast places in the middle of discussing tea, desert trend themes, and foodie culture but it does connect.

not exactly nailing the updated diner theme

The common ground relates to the source of trends not always being so trendy where they are from.  A traditional Chinese tea shop or cafe would be a run of the mill thing in China, but in North-Western PA it would seem very exotic.  Who knows when they'll ever get a Thai restaurant back there but here it's grocery store complex food court fare.  Mexican and Italian food restaurants that go out of business due to lack of interest back in the States could potentially match the best related foods versions Bangkok has to offer.

Pancakes are sort of the same here; a bit exotic.  I was a little shocked and horrified that they didn't have bacon, sausage, or hash browns on that I-Hop menu, and I'm still a little rattled about it.  I was a vegetarian for about 17 years so I can take or leave meat more than most but it's still disrespectful to the theme of American breakfast.  It's downright un-American.  Somehow waffles are common here but french toast and pancakes not so much; I'm not sure how that worked out.  Sausage is common here but  Jimmy Dean-style breakfast links would be as out of place as dim sum or pho back in the Midwest (or som-tum, Thai papaya salad; you get the idea).

If this was going to circle back to tea it probably should have already.  Those recommended cafes work as a transition; the two new ones and one older version sum up what's going on in Bangkok.  TWG is on the list, and Twinings cafe might as well be, and Whittard I just walked by in Paragon.  High end commercial, traditional versions of tea aren't really of interest to me.  The one Japanese tea shop sounded nice, and that was about it.  People probably bought more matcha drinks at those booths in that mall event over the last ten days than traditional pots of tea at all of those other places combined over the same time frame, or maybe a factor of ten more.

I'm behind in trying different flavored ices

It seems odd to conclude that only matcha is even close to being the hottest latest trend in tea in Bangkok.  It'll be funny if "cheese tea" really takes off.

Good oolong or pu'er teas just don't seem to fit the mold of what catches on (or mould, for British people).  As with in the US better tea may just gradually ramp up for years until it finally really catches on, and if that seems to happen suddenly the reasons why will probably only make sense in retrospect.  

Monday, August 21, 2017

Comparing Yunnan Sourcing Liu Bao and Shou Pu'er

2012 Three Cranes 25017 Recipe Liu Bao

2016 "Golden Fruit" Menghai ripe / shou pu'er cake

Of course it would've been more descriptive to put what the teas actually are in the title, not the vendor name, but the word count runs long.  Here are the descriptions for a number of hei cha I recently purchased to get around to exploring the general type more (along with one black tea a friend recommended, the same friend that recommended the shou):

So there they are; one I'm comparing in this review is the first, a 2012 Three Cranes 25017 Recipe Liu Bao, and the other is a 2016 Menghai "Golden Fruit" Ripe Pu'er, or shou, as I tend to call the type .

I've tried the shou twice already; it's nice.  It would work to review these separately, but comparing them cuts the number of write-ups in half, and adds the direct comparison aspect.

Often comparison is about highlighting subtle distinctions, enabling appreciating something about a feel aspect, for example, or noticing a slight difference in complexity, but at first taste that's not how this is going to go; they'll be quite different.  It's probably mostly just about how I review but I tend to say more about feel and aftertaste aspects when doing individual reviews, and focus more on taste in comparison, as I see it because that level of detail is natural to notice first, and description of it already runs long.

The scent of the Liu Bao is earthy, musty even, like someone's basement.  Not the clean "game room" sort of environment, where there is wood paneling and the old version of living room furniture and a pool table down there, it smells like a musty cob-web covered storage place for jarred food.  It'll be fine though; I don't mean that as saying it's not nice tea.

The shou is good.  I can go ahead and pass on some prior impression before tasting notes.  There is no mustiness to it, it's not overly earthy, no petroleum or tar, and definitely no fishiness.  It's smooth and rich, full in flavor, but to me not necessarily complex in the sense of lots of distinct aspects coming across.  I mostly just get "shou" range from it.  It's good though; well balanced, complex, smooth, and sweet.  The effect reminds me a little of that rich earthiness in Guinness Stout, just not quite as creamy, which to me is very positive.  It's especially nice for containing no negative aspects or roughness at all, so you can drink it at any infusion strength, even really thick, which I just confirmed the second time I tried it.

the shou ("ripe") label

Some background

These posts really do go long enough as it is but I wanted to mention a couple of things first.  Someone reviewed this shou version in a Yunnan Sourcing Fans FB group, and that makes for a good chance to pass on another impression, especially given how developed a flavor-list description was in that:

Nose is wonderfully complex for such a young shu puer: sweet and malty, leather, wet bark, dried figs, brown sugar, caramel are some of the things that come to mind. There is a hint of peach, but it's very subtle and it disappears after a few steepings. Taste is full and creamy, with notes of dark chocolate, licorice, wood and hazelnuts.

I tend to either avoid reading other reviews before trying a tea (most typically), or in some rare cases I intentionally do, but this was in the middle, since I read it by chance a week before first trying the tea and two weeks before this write-up.  For better or worse with my memory that means it wasn't accessible to me in doing this tasting since lots of lists of things, names, and numbers just don't stick for me.  Abstract concepts, events, and personal interactions do; funny how that works.

This is a good place to pass on the Yunnan Sourcing product description too:

The idea was to create a peach taste in the ripe pu-erh.  At this early stage it's hard to taste peach but there is a fruitiness thats developing in the tea and that long-lasting feeling in the mouth that transforms into sweet on the tongue.

Reminds me a little like that hui gan post theme even though it's not really about the same idea.  I may as well pass on the other Liu Bao product description while I'm at it, which goes into storage conditions:

25017 is the recipe number for this traditional medium level fermented Liu Bao tea from the oldest producer of Liu Bao in Guangxi (Three Cranes / Wuzhou Tea Factory)...  The 25017 is wet piled for about 29 days, which is typical for classical Liu Bao.  The result is a liu bao with some bitter, sweet, chocolate and betel nut flavors.  It's got an obvious "chen xiang" (old taste) due to classic style processing and 5 years in hot and humid Wuzhou storage condition.  This has been stored since 2012 and then in 2014 packed into 15 kilogram baskets. The wet storage conditions in Wuzhou have fast aged this tea, but at the same time the tea is not funky or moldy.

comparing dry versions; shou left, Liu Bao right


On to actual review then.  In order to see all of what's going on with these I'll taste the initial infusion (the rinse) but it would probably be a good idea to always do a quick rinse that you don't drink with shou and aged sheng.  I've cited a research article in a post about factors in fermentation that covers one reason why before, about them containing some traces of toxins as output of the two related fermentation processes (related to a role played by fungus and bacteria in both shou and aged sheng).  That's perhaps not exactly standard fermentation, related to another good source description, since the process is based on air contact, but lets stick with that instead of a term that means nothing to most people (microbial ripening, described in that Tea Geek blog article).

I'll start the review on the second infusion, starting out brewing the two teas on the light side.

Liu Bao:  I'm getting a good bit of "damp basement" from this tea, as the scent suggested.  It really takes me back to my brother and sister and I locking each other in a potato storage cave-like basement area in an old house we lived in when I was young (in PA), one of the mustiest places I've ever been.  Oddly that's not all bad.  Beyond the damp earth and mildew tastes mushroom or some other type of fungus comes across next.  That last part is like the scent of the half-moon shaped fungus that grows on trees; earthy in a unique sense.  The tea has redeeming aspects and character, and I suspect it will clean up a bit after another couple of infusions.  There is some sweetness to it, and richness, and other depth, and it comes across as more "clean" than it probably sounds.  At this point in the infusion cycle it's hard to summarize the overall experience as "I like it" but the tea seems to have potential to show more.

The shou is earthy but very clean in comparison.  There's a molasses-like sweetness that really compliments the complex range of other earthier aspects.  It doesn't remind me of peat much at all, as some shou tends to, certainly not of mildew or fungus.  One aspect is towards walnut or roasted chestnut.  Some of the range is a bit towards forest floor, but a clean version of it, the dry-leaf style of an autumn forest, not the damper and peat-like character of a spring forest.  The complexity extends a good bit from there, it's just hard to split into components.

It's hard for me to compare against other better shou I've tried since the two other shou versions I've bought this year weren't quite this good (a standard type of brick and a tuocha).  I think the brick version could potentially have expressed a bit more range of complexity but then that tea, a three year Kunming (aka CNNP, formerly) 7581 brick, tasted a good bit like tar or oil; not really what everyone is looking for in aspects.

Per one take once a shou loses the initial fermentation effect off flavors after a couple of years they don't transition that much.  Per an opposing take they do keep changing and developing over time.  I don't have lots of opinion on that, or enough experience for it to follow clear trends based on what I've tried.  I compared multiple years of one classic shou version quite awhile back (7572 cakes, with those listed in the YS page here, or with a little about that in this post) but attributed the differences to yearly differences in versions, and had little to go on for shou exposure at that point.  More so now but I guess there are levels to that; this is the third I've reviewed this year and I'll probably leave off them for awhile.

shou left, Liu Bao right (both a bit thick looking)

Second infusion

The infusion time was relatively fast, 20-some seconds, but these teas still brewed to be thick looking, a dark reddish brown.  I might try a flash infusion next time to experience them thinner.  I've tested this shou at ridiculous brewed strength the second time I tried it (earlier), going with a really high proportion and even longer times, and it works well across the whole range of however you make it.  Sometimes teasing individual flavor aspects apart for description works better lighter, and I guess personal preference steers what range is most enjoyable, for me different for different teas.  I don't prefer most tea types as strong as possible, and some work lots better much lighter, even without brewing around astringency or whatever else as a factor, but I do tend to like shou on the thick side.

The Liu Bao is cleaning up in character, although it would still be one of the earthiest and mustiest teas I've ever tried as it comes across now.  But it's still nice; cleaner, with good complexity, lots going on.  I think I like it more because of the novelty than the aspects range.  The richness in taste extends a bit towards coffee, maybe leaving off a little short of that, closer to tree bark.  The mustiness has backed off so it's just a supporting aspect, not so negative since I don't mind it.  With the flavor range "cleaner" it comes across as sweeter.  There's a little wild mushroom in flavor but it's not so much tree fungus now as portabello mushroom.  I suspect the tea will really show it's potential in the next infusion.  I wouldn't be surprised if the bark moves just a little into spice, but we'll see.

The shou isn't so different than the last infusion, maybe just a little cleaner and sweeter, but still grounded in a subdued earthiness and complex.  Sorry about contradicting myself related to that, but in one sense it's rich and thick and complex, and in another perhaps a little thinner and simpler than it might be.  Writing literal contradictions might not really seem descriptive.  The taste level is full enough, but there is some range it might be hitting that it doesn't get to, and the feel could be a little fuller, but it is fine as it is.  For a very reasonably priced tea it's quite good.  It is strange to hold a tea to perform up to a price level, and not just examine it for what's there.  I think the same yardstick applies to the Liu Bao, as I remember pricing; it compares well to expectations for teas that don't cost a lot, to the extent one is on that page for evaluation, although that type of musty earthiness wouldn't be for everyone.

I like this shou brewed at this relatively conventional infusion strength but somehow it sort of makes sense to double it, as I did the last time I tried it.  Maybe that's only because it's possible, because it doesn't have any negative aspects that would also double, more than as a criticism about it gaining the effect of complexity and intensity at higher than average brewed strength.

Third infusion

This time I did infuse the teas for about ten seconds, not really a flash infusion but on the short side.

The Liu Bao is the best it's came across prepared this way, which I suspect is as much due to prior rinsing as being prepared lighter.  That earthiness might not really drift towards spice but it's cleaner yet.  It comes across a lot more in the range of tree bark than fungus now.  I suppose others might be split on the complexity really relating to forest floor versus a clean version of peat.  It has a compensating sweetness, and mineral tones, and I suppose with enough interpretation someone could taste out a dried fruit aspect of some sort in it, maybe dried persimmon.  It all works.  It would be way too earthy for a lot of people's preferences but I like it.  I probably wouldn't want to drink it all the time but I could imagine it working as a breakfast tea, or with an afternoon snack, a tea you don't need to focus on that would pair well with some compensating sweet food.

Trying the tea later, in a tasting after this first round, this Liu Bao tasted exactly like brewing charcoal to me.  Now I wonder if it transitioned to that across the infusion cycle or if I completely missed that "mineral" I just mentioned tasting like brewed coals, like carbon.  That's one reason why it's better to try teas a few times for review instead of just writing notes on the first go:  beyond separating out one or two more vague aspects it is possible to completely overlook a primary taste, or "feel" aspect.  The shou doesn't really change.  It doesn't lose much for being prepared quite lightly, although I'd naturally tend to make it a lot stronger.  

The idea of preparing these lighter supporting ease of breaking apart flavor aspects isn't working, but per usual the chaotic background in this house isn't helping with that either.  As a tea-friend put it, tasting works best in a meditative space.  My son has some idea about playing he wants to get to, and my daughter just stamped me three times, the kind that they put on letters, or to show paid entrance to a bar.  But it's the noise that's worse relating to focusing.

she seems low on ink

Anyway, this shou is drifting a little into a spice range, like the darker cinnamon a Rou Gui can show, but still light, with plenty of sweetness.  The sweetness reminds me of caramel, but that could as easily be toffee, or molasses.  I suppose it could taste just a little like peach.  It has a brightness to it, versus a heavier tone one might expect.  The range that is there is quite positive; if there is a weakness to the tea it might be that range not suiting preference, or that it could be a bit more complex.

shou left, Liu Bao right

Fourth infusion

Apparently I really do need to go play so this will be it for the tasting cycle but I think these teas have a good bit more to show.  I'll go longer on this infusion to see how that works out, more like 45 seconds versus 10 the last time, after just under 30 the others.

It's interesting how much that changed the character of the Liu Bao; I take back that guess about the rinsing being a bigger factor than infusion strength; both seem to be factors.  An underlying trace of mustiness remains but this tea is now mostly just earthy, and intense, at least at this infusion strength.  Instead of tree bark this now reminds me of the scent of very old aged wood, of how a 100 year old barn smells.  I could imagine people hating that but I can kind of connect with it.  It's probably cleaner in effect than it sounds.  The tea is also complex, in a sense, but a list isn't coming to mind.  With mineral on one "lower" layer and sweetness on a higher end the aged wood and tree bark fill that in, not really extending into spice much, maybe a little towards an earthier root spice, that hard to pin down range of ginseng, for example.  It must have tasted like charcoal at this point but later infusions went to straight charcoal.

that one trouble maker

The shou is the same; that's going to save on some words.  And I've nothing really to add or conclude at this point in tasting; I liked it.

Conclusion / one more experiment

It's a bit insane but I tried out cold brewing the shou based on trying it yesterday, to get the last of a round of infusions out of it.  In reading up on fluoride levels in tea--there's low risk related to overexposure to that, don't worry--one set of tests said that using a very long infusion time is a good way to extract a lot of it out of tea.  Old tea plant leaves have the most fluoride content by far, per hearsay with that working out to much higher levels in some types of hei cha.  So I might've just been dosed with lots of fluoride.  Per all that research plant leaves from the newest leaves and buds contain the lowest levels and I do tend to drink teas made from those regularly.

The shou is interesting (the other version, from yesterday, the cold-brewed tea).  It's really sweet for some reason; I might even finally be getting that peach.  The taste range is in between fruit and root beer.  It's different; worth a try.  It's strange drinking the tea cold, after the past hour of hot tea tasting in the same general range.  Somehow it makes a lot more intuitive sense to drink other teas cold, black tea, of course, or lighter oolong, but this being as sweet and light as it is helps it to work.  It's not an overly earthy shou brewed hot anyway.

It's also strange tasting the cold version right beside the hot version (a bit cool now; this is taking forever with all the messing around).  It could just be me, or that the cold version was relatively brewed out prior to spending the night in the fridge, but a different aspect range seems to come across a the different temperatures.

As for other conclusions, about the Liu Bao versus the shou, both were nice.  I think I probably liked that Thai Liu Bao I tried not so long ago better, maybe partly since mustiness wasn't a factor in that.  This one is still interesting to me, and generally positive, I just wouldn't want to drink it very often.  Probably the 100 grams worth I have will be enough, or 50 might have been ok, and I can share some.  A Malaysian online friend is really into Liu Bao (which also goes by Luk Bok there), the same one that passed on that input about "gan" in discussion of lui gan in a recent post.  If something comes of input from him versus a standard range of aspects versus what I'm describing I'll pass than on.

About Yunnan Sourcing and international shipping

If any readers aren't familiar with Yunnan Sourcing--which would seem a little odd, to have never heard of them--it would be a good idea to check some of those vendor page links.  They sell an incredible range of teas, lots of types beyond pu'er, so the focus isn't on curating a limited theme of offerings.  To find out more about specific teas places like personal blogs, that Yunnan Sourcing group page, or Steepster could provide additional feedback about them.  It's hard to know how to take one person's opinion based on only reading about unfamiliar tea versions, since preferences and expectations vary, but comparing a few opinions helps counter that.

There was just a discussion about shipping issues in that FB group, related to the timing communicated not getting the point across (they are based in Yunnan, China).  I mention it here since it helps fill in expectations related to buying teas directly from overseas.  Most discussion and comments were about the estimated delivery time descriptions in the options being generally accurate.  Mine came faster than the estimate, but then I live in Bangkok; we're neighbors.

Someone just commented elsewhere that shipping from China to the US costs $22 for a 600 gram package, in case that's helpful, but the way that site is set up there are multiple options, with faster versions costing more, and slower versions less.  At a guess that rate would be for a medium time-frame delivery.  It doesn't seem to matter so much to me if tea takes two weeks versus a month to make a trip but the estimated range for slowest "surface" delivery (sending it by boat), is 36 to 61 business days, and that could test one's patience.  I suppose it's worth considering that it's also the most environmentally friendly option.

I'm guessing this range is for a good bit of tea (credit YS Fan group post)

Thursday, August 17, 2017

The real meaning of hui gan

I have no idea what hui gan means, personally, although I've read lots of discussion about it.  One thing seems clear:  people are using the term to mean different things; they subscribe to a range of varying definitions.

Not unheard of in this blog, I won't be offering much of my own opinion.  I just ran through a similar post context in reviewing a blogging life-cycle, related to people stopping blogging about tea, in which four other people that did that passed on their own insights.

The experience of tea is what it is, regardless of how it is parsed or described, and to a limited extent adopting foreign concepts to frame my own experience isn't a personal interest.  In writing this tea blog I struggle to separate flavors into parts, into an aspect list, and do something with relating the experiences of feel and aftertaste, but my success at any of the three seems limited, to me.

But in this case the concept of hui gan has came up a few times recently and I want to pass on some ideas from that.

I'll start with a more literal and basic definition, from Bablecarp (a tea term definition database):

hui gan (Hui Gan) = pleasant aftertaste, literally Returning Sweet (回甘) [2,1]; or, much less commonly; also, a non-specific label for virtually any effect after the liquor has been swallowed, literally Returning Feeling (回感) [2,3]

Posting that very citation in a tea group is what drew me into this concept and subject, in the form of a Chinese Malaysian online friend sending a long rejection of that definition and explanation of "gan" by message.

I'll get back to that part, and start with another article reviewing the concept I've read since then.  The whole article really deserves a read, even if someone disagrees completely with the interpretation after going through it.  Here are some parts of a recent "Going, Going, Gan" article in the Cleaver Quarterly, written by Angie Lee (which really doesn't summarize by citation well, but doing so will provide access to most general points covered):

I have been to a tea master’s shop in Hong Kong where he brews a pot of Pu’er tea, pouring it into cups no larger than thimbles. We drink it down. There’s a fragrance, with a slight astringency, at first, and then layers of other flavors – tangy plum, honey, and sweet citrus – pile on, and the liquid tastes thicker than water.

The tea master looks at his watch, counts to 15, and exhales. We wait. And then it comes. Sweetness in the back of my throat and a cooling tingle on the sides of my tongue, goosebumps up and down my arm, hairs at a salute. A few of us look around as if the air conditioning has just kicked on... 

Select foods are known to produce gan 甘, this sweet-tasting, air-chilled sensation that follows an initial sting of bitterness. Gan is peptic, but also poetic – the quicker the conversion from bitter to sweet, the more desirable, but there is no shortcutting the bitterness. Gan is an afterimage.

So far so good.  In tea circles it's often used in the form of "aftertaste," but somehow there is always more to it.  I could almost stop at this point, since it's not as if more explanation makes it any less vague.  Maybe the opposite is true, and it ends up making less sense, as further citation of that confirms:

Not surprisingly, all gan-producing foods are native to China... 

Translate gan from Chinese to English and you get “sweet,” but go the other way around and sweet will always register as tian 甜. Tian is sugary, tian is when someone is being sweet to you, tian is what you say when someone is being a kiss-ass...

Gan is not just a taste, it’s an often-eerie sensation that something or someone has come and gone. A little like the way “bittersweet” is used more often in describing a relationship rather than a specific taste. No food actually tastes bittersweet. 

Gan is found in ginseng (a rhizome valued for its medicinal properties and resemblance to miniature humans) as well as in licorice root (not the red twisted candy), but not in star anise or anything made with anise oil, which tastes like licorice without the special bitterness. 

...Lastly, gan is found in Pu’er tea picked from old trees. 

As you read the rest it becomes even less clear what "gan" is, not more so.  That last citation already contained an example:  ginseng has almost no taste at all (the root and related tisane infusion), so it could hardly be aftertaste, in any normal sense.  That ties into the conclusion:

Unlike its friend umami, whose tongue-tingling delight ends as soon as it’s swallowed, gan isn’t a flavor...  Gan is curious. Gan is a transformation that may or may not happen. We may fail to find it, or have a muddling of sensation – no returning sweetness – but the act of listening transforms the moment.... Gan is a gift, and it’s neither here nor there. If you’re lucky, it’s a glorious buzz, this muddy footprint, this temporarily sunning dog.

this guy gets it

It sounds a bit zen-like, as if not making sense is part of a designed approach here.  A commenter on the Facebook page post for the Cleaver Quarterly was not impressed:

The overall content leads one to believe the author does actually know "gan", much less how to describe it. But without going further into minute details or refuting every bit of factual error, I will make just one point: contrary to what the author thinks, gan is not social, it's not philosophical, it's NOT "curious", it is as solid as salty, sweet, sour, pungent, or bitter, and every bit as REAL a flavour as any other organoleptic sensation. And if the author does not cannot see that, I don't know what to say.

No hint there what gan actually is, in that comment, never mind hui gan.  To me that's bad form, to criticize ideas without actually adding a specific criticism.

Discussions in tea groups turn up alternative definitions, like this one in a Reddit thread, or this one on Tea Chat, or one that started 13 hours ago in a FB pu'er group based on this article posting (at time of first draft of this post).  A lot of reading only broadens possible meanings, it never settles into a narrow range.  It means something like aftertaste, or feeling, or both, or something else.  

Again I'm only passing on other people's ideas here, and my friend's explanation goes long, so I'm going to cite that and be done with it.

A Chinese Malaysian friend weighs in on the meaning of "gan," edited

After a longer explanation of "gan," which I'll get to next, that friend passed on this summary of the concept:

Often times, both taste and sensation could be felt, simultaneously. It is not uncommon for a person to make the funny sound, similar with an animal lapping water, with quick movements of the tongue tapping the roof of the mouth to savour '甘' or 'Kam', an awareness more than a sensation but not a flavour proper per se I had mentioned earlier, whilst experiencing bitterness. Perhaps the 'sensation' or 'awareness' of '甘' or 'Kam' could be closely described as having an ice-cold fingertip gingerly brushing the back of one's neck. Such a feeling is felt sporadically and enveloped the rear of the tongue and the soft palate of the mouth. Others might have different description.

So far so good.  I like his writing style, by the way, very clear and precise, with a tone that reminds one of reading a classic novel.  That's the clear and simple summary version; here goes with the longer explanation:

First and foremost, the character, '甘' or 'Kam' is not 'sweet'.  Then, what does '甘' or 'Kam' truly mean?

The expression 'Kam' is only suitably used if it involves Chinese medicines, certain vegetables, fruits and nuts, such as bitter gourd, some pomelo and walnut, repectively. Of course, our favourite drink, tea.

What is the similarity shared amongst these foods? The crucial characteristic with all these foods is bitterness. It is therefore, for one to really find 'Kam', the food itself must at least has a hint of bitterness.

To further explain 'Kam', it is inescapable to explore a few Cantonese phrases. 

'苦口良藥' pronounced as 'Fu Hau Leong Yeok', means 'Bitter medicine provides good remedy', a phrase often used to cajole a sick person to take the Chinese medicine. 

'甘甘哋' pronounced as 'Kam Kam Dei', having '哋', a combination of '口' or 'Hau' also 'mouth' and '地' or 'Dei' also 'ground', is strictly a Cantonese characters, provides the meaning 'a little bit', thereby making '甘甘哋', a conversational Cantonese, exclusively, referring to tastes and flavours.

Both the phrases, '苦口良藥' and '甘甘哋', are usually used together, it means 'Take the medicine, although bitter, it also tolerable as it tastes Kam'.

Unlike those distinct tastes of being categorically defined as sweet, salty, sour, hot and bitter, 'Kam' is neither a taste proper per se, nor 'pleasant' for the lack of accurate and better description, but it is more than a sensation or awareness that lingers in the mouth. 'Kam' is a redeeming or compensating feature of bitterness and for it to manifest itself, there is a prerequisite that the medium being savoured, must be bitter or at least a tinge of bitterness. However, not all bitterness would necessarily has 'Kam'.

'甘' or 'Kam' is not 'sweet' because in Chinese, 'sweet' is '甜' or 'Tim', certainly not the intention of the creator of these characters to have them used interchangeably. A Chinese character could always be used unaccompanied or in combination with other letters, in various situations creating nouns, verbs and adjectives. However, it is not common to have different characters describing the same taste, creating redundancy. It is well known that amongst the many difficulties of learning Chinese, especially Cantonese is its uncompromising jigsaw puzzle trademark, both in writing and in conversation, requring precision in numbers of strokes of a letter and pronunciation, respectively, having each character applies to each situation, tastes in particular.

Perhaps, the words '甘蔗' or 'Kam Jeh' also known as 'sugar cane', a noun, had somehow provided the confusion that '甘' or 'Kam', an adjective, is associated with 'sweet', merely with the existence of the word 'sugar'. However, with '甘蔗', the letter '甘' is not used to refer to 'sugar', the character '蔗' or 'Jeh', a standalone character in itself, is sufficiently understood as 'sugar cane'. 

Also, '竹蔗' or 'Juk Jeh', a variant of sugar cane, boiled in a pot of water for its stock, used as traditional remedy to reduce discomfort caused by measles and mumps during childhood. The liquid is not as sugary as sugar cane juice, but leans towards bitterness, it qualifies as Kam. Therefore, normally '冰糖' or 'Bing Tong', means 'Crystal sugar' is always added as sweetener.

I strongly believe that '甘' or 'Kam' being defined as 'sweet' is a lazy and reckless decription offered to others especially to the western society and younger generation of the Chinese, without giving much thought that by so doing, would deny the true identity of '甘' or 'Kam', vis-à-vis taste or sensation... 

...Please remember that I am not here to convince your goodself of the precise definition of '甘' or 'Kam', because there is no specific English vocabulary providing the corresponding designation to this Chinese character used to define the taste or flavour, but only to identify with absolute certainty the error and fallacy of equating '甘' or 'Kam' with 'sweet' or 'pleasant aftertaste'.

Just like any other Chinese characters, '甘' or 'Kam' is a mere ordinary letter, even in combination with other Chinese characters, but if it is utilised to illustrate foods, a more detailed narrative is needed to properly explain this letter in relation to 'sensation'. 

Other references

After all that it would be easier to stick with "aftertaste" as a definition, but to the extent that I understand it I trust that friend's summary.

Or one could just go with nonsense as a final summary, as in the Cleaver Quarterly article, that it's something that absolutely can't be described.  That final Zen koan definition was that "it's a glorious buzz, this muddy footprint, this temporarily sunning dog." Mind you parts of that article were simple and clear, and did match the rest of these other ideas better than that conclusion, but parts of it also seemed to directly contradict other parts.  But then sometimes complicated ideas can be like that, a bit irreducible.

Or that Reddit thread discussion I had mentioned passed on a nice simple version in the introduction (here related to hui gan, since the term as used to describe an effect of tea is expressed as both characters combined):

Some people say it's a sweet lingering aftertaste rising in the back of your mouth after swallowing.  Some people say it's a cooling sensation (something like what menthol gives) you feel in your throat and back of your mouth after swallowing.

One could just go with one of those definitions, or both.  I turned to one of the classic blogs for a final working definition, the Tea Addict's Journal, and didn't find one there, but I did find a summary of some general ideas that relates:

From observations and discussions with other tea drinkers, I think after a while, we all move, slowly, towards a deeper and more subtle appreciation of tea, and that means that we start moving away from just looking at what the tea taste like, and put more emphasis on what the tea feels like. Good (and usually expensive) teas invariably feel good in a way that inferior teas do not.  They don’t always taste all that different, however...

...The chief difference among them is the feeling you get from the tea.  What I mean by that is not that it makes you high or your head spin or what not (although I suppose it could do that).  Rather, it is the physical sensations that you have in reaction to, first, having the tea in your mouth, down your throat, and then the reaction that your body has towards it that distinguishes the better from the not so good.  A nice one is full, thick, smooth, hits all corners of the mouth, leaves a strong, lasting aftertaste, stimulates the tongue and throat, and gives you a feeling of qi.  Bad ones are just a beverage — you taste it, it goes down, it’s over.

I think the subjective perspective focus here, in terms of this relating to a specific form of individual experience, not in terms of it being not-objective or made up, could easily be overlooked or misplaced.  Regardless of the extent to which there is one specific, limited range of experience that relates to gan / kam, and there probably is, it only means something to someone once they learn to relate to that experience.

Getting the labeling right--partitioning off specialized terms to identify limited experience range--is only a part of that, and probably not the most important part, although using the same terms in the same ways would help with communication with other tea drinkers.