Created: Aug 16, 2021 • Modified: May 28, 2022

Collection of thoughts, notes, and reviews of loose-leaf tea and other water infused beverages that I’ve tried, including experimentation on custom blends with herbs, flowers, spices, berries, steeping methods, and roasting. Maybe some content about similar beverages like coffee as well in the future (though I prefer tea to coffee). The info on this page is mainly for myself so that I can remember things like what I enjoy, what I hate, the ingredients in blends I’ve created, and specifics for replicating the taste. The appendix contains some of my own insights on making tea outside of the actual tea itself.

Preamble

For each tea, I try to provide a photo of the label (if present) which typically contains important specs such as where the tea was grown and various related notes (they’ll mostly be in Chinese though), and links to external articles for my own future reference.

A quick summary of my tastes: I enjoy nearly any category of tea, and I mostly drink Chinese teas. No matter how good a tea is at first, I get weary of it after two or three days of consecutive drinking (until I take a break from it, then I’m back to loving it). I find that I need to alternate teas every one to two days and frequently create new blends to keep my interest. I buy teas pretty much exclusively through local stores, I enjoy supporting local businesses, or directly imported from tea farmers I am acquainted with in China.

I use a ceramic mug that was gifted to me a few years back. It comes with a lid and a large basket filter. A large filter size is important because it allows the leaves will also unravel and expand when steeping, and a large filter will allow the leaves room to spread out, leading to higher quality tea, specifically more unami due to more surface area. I like my mug in particular because of the shape, the bottom is wider like a traditional teapot which keeps the temperature of the water reasonably consistent.

The drinking water in my house is filtered through a reverse osmosis system which removes some potentially unwanted chemicals and a moderate amount of minerals (of which there is an excess of in the tap water where I live). I have a softener which adds back some mineral content after the water is filtered.

See Appendix: Thoughts on Teaware, Water, and Materials for my take on various external aspects of tea.

Teas

Light

Whites, yellows, greens.

Anji white tea

[wiki] A fairly uncommon, rare (and expensive) tea grown in Anji County in China. Technically, this is a green tea, but to me it has more in common taste-wise with white teas.

Taste: A balance of nutty and vegetal.

XiLongXianZi. [spec1 spec2] Smooth, buttery, grassy. Quite pleased with this one. It took a few tries before I was able to get the water-tea leaf ratio correct because it was weaker than I expected. Flavour is quite similar to a typical green tea, but with a deep rich weight and a strong, almost milky taste. The texture is silky smooth. Overall, I was very happy with it.
Unbranded pack, unknown origin. Season to season differences are purported to be a fairly substantial factor in these teas, so I expected a different taste than the older pack. This pack was noticeably lower quality, and didn’t have quite as thick or smooth as a feel as the XiLongXianZi pack. I was able to replicate the rich, dense, milky unami of the older pack, though it was inconsistent (I was only able to do it sometimes). I tried adding more leaves, using slightly hotter water, and longer steeping times, and rather than return a more savoury flavour, the tea would ‘scorch’ and taste ‘burnt out’. Though the tea was whole leaf, the leaves started breaking and crumbling after three to four infusions, a sign of lower quality.

Xue Shui Yun Lu

A relatively little known tea outside of China. It’s name translates directly to ‘snow water cloud green tea’. The pack I got was fairly oxidized and darkly roasted for some reason, which made it taste similar to barley tea, but more watered out and leafy. I didn’t quite like it, and it was certainly not what I imagined to be ‘snow water cloud’.

Xi Hu Longjing

[wiki] One of the ten famous teas, and is probably the most prized green tea in China, and certainly the most artisanal of the Longjing teas. It has a subtle, slightly sweet, sharp tone. The pack I got was fairly very good quality, the leaves were uniform, and not too dark. Unfortunately it did not seem like a premium early season picking, but was still good nonetheless.

Dark

Black, oolong, and similar. Not including pu’er, separate section for that.

Da Hong Pao

[wiki]A very fragrant oolong tea grown in the Wuyi mountains that is personally my favourite type of dark tea. Here are the brands I’ve currently tried. Currently only one because this tea costs a pretty penny.

Tasting notes: mineral, smoky, nutty

Weng Royal Commodity. [specs] A gift from relatives, probably the priciest tea that I have ever drank. My first taste of a Wuyi tea as well as my first time trying one of the Chinese ten famous teas. It has a very delicious flavour that is quite a bit smokier than most other dark teas, probably because it was fairly heavily roasted. There is a hint of sweet nutty tone which goes particularly well with sunflower seeds. The tea tastes significantly better during the second to fourth infusions, which bring out the nutty tones in particular. It also lasts a long time, I’ve done as many as fourteen infusions! (can’t waste good tea) It is definitely one of my favourites. I’m glad it was a gift because I doubt I’ll ever have the resoluteness to spend the money to buy it myself.

Dian Hong

[wiki] An interesting kind of golden black tea with emphasis on golden buds, thus making fairly expensive to grow (less weight due to getting the buds only). Brews a soothing amber in colour (which I really like), and is different from most other black teas in that it is mild, docile, while retaining a full character. The taste is very impressive due to the balance between black tea sharpness and a sweet, ory taste.

Taste: malty, mineral, cocoa, sugary

Jin Zhen (golden needle) - A 2021 pack. The quality was on the higher end of moderate, not bad for the price I got it at. It was surprisingly sweet, almost no bitterness except when I brew it too long. The aftertaste is very nice, a nutty, but sweet flavour.

Formosa (Taiwanese tea)

[wiki] Darker versions of Taiwanese tea are here. If I ever try lighter types of tea from Taiwan, I will put then in the lighter teas section. Taiwan is famous for it’s oolong tea in particular, though I haven’t tried many varieties (in fact, only one) so I don’t have much to compare to.

Amis tribe ‘Zhu Tan Gong Fu Cha’. [specs] A Taiwanese rolled oolong tea pack I (again) got from my relatives. I’m not sure of the exact processing and origin, the package is unclear, though it is referred to as a tea of the Amis people, so looking at the traditional territory region of the Amis, it is likely that the tea was grown on Eastern Taiwan, probably near Ruisui (where there is a tea farm). For some reason it has no certification mark indicating this, so I conjecture that it is low grade. I’ve never heard anything of zhu tan tea (meaning ‘bamboo charcoal tea’) either, I presume this means the tea was roasted over bamboo charcoal, which if so, means that it may be more valuable than I expect (bamboo charcoal is expensive). The tea was packaged in triangular teabags, even though it is whole leaf. In order to let the tea leaves expand, I took the tea out of the bags before steeping. It has an interesting floral nutty flavour, maybe it really was bamboo charcoal roasted, though I don’t think the leaves themselves are high quality. I noticed they only last about one to two infusions before losing the great majority of their flavour.

Ding Dong

[wiki] Woody, light flavour, good for average afternoons where one isn’t particularly sad but not elated either.

General taste: fresh, sweet, mellow, grassy

M. Nen Yu - Very pleased with this one, I drank it purely for a week once and still doesn’t bore me. I am surprised how many infusions they can take (sometimes I start grandpa style in the morning and I can still squeeze flavour by bed time).

Tie Guan Yin

Muzha, Aged since 1996 - Obtained online, smells more earthy than most oolongs, slightly burnt, quite dark and dense. Its not a metallic dark though, more like astringent burnt dark. Aging oolong likely brings out more astringency than I would enjoy paired with earthy taste. I enjoyed it, but it wouldn’t be my goto (ding dong for that).

Pu’er

Various varieties of pu’er that I’ve tried. In my opinion, the specifics of the tea factory, roasting (if any), and fermenting process for pu’er is more effectual on the taste and quality rather than where it was grown (which will probably be Yunnan anyways).

Xiao Qing Gan

Xiao Qing Gan is pu’er that stuffed inside a small tangarine peel (typically green, not ripened yet) before fermenting, giving the tea a slighty tangy, sweet tone. It is my personal favourite type of pu’er. Almost all xiao qing gan teas follow the same recipe: A Yunaan pu’er and a citrus from Xinhui, Guangdong, and as a result taste more or less the same. Here are teas from various factories I have tried:

Shen Ruo Tea Co. Ltd. [specs] Based in Jiangmen, fermented for 8 years. It was my first time trying pu’er tea, and I fell in love right away.
Di Bao Pao Trading Co. Ltd. [specs] Also based in Jiangmen, specifically the Xinhui district. Label mentions no specifics on processing, fermentation time, or even the precise origin of the pu’er (though it is very likely from Yunaan). I infer that it has been fermented more than the Shen Ruo one because it is slightly darker.

Jasmine

[wiki] Tea that has been scented with the notorious, night-blooming, jasmine flower. Although I’m fine with the taste, teas infused with stronger jasmine does hurt my throat after a while.

Yin Hao - Affordable and delicious. One of what I believe to be the best pairings of Jasmine and tea. The fine silver tips, due to them being small and able to absorb the flavour of the jasmine quickly, make this tea fairly easy to produce but still high grade.

Infusions

Other types of steeps not necessarily made with Camellia sinensis. I included this to note the specific flavour of various herbs, flower, spices, and such inside water. This is useful to know for creating blends with the other teas above, as well as pure tisane blends.

Honeysuckle

Slightly bitter flavour, but also has sweet tones. It produces only a slightly tinged green coloured liquor, and was also not as fragrant as I expected. Nonetheless, it is very soothing for the throat.

Peppermint

Minty flavour that is very aromatic and relaxing to drink. Goes well with honey and lemon, though I often prefer it plain.

Black Goji Berry

Not to be confused with the more common red goji berries. Moderately sweet and slightly aromatic. Steeps purple. Goes well with the bittersweet flavour of rose. Mixing in a small amount of lemon juice turns the tea from purple to pink.

Grains

Barley

An interesting nutty flavour that is good with cake or biscuits. It is fairly weak and I find that it oftentimes requires a steep time of around 7 minutes, at least with whole barley grains. Combining a some barley with black and darker variants of oolong make for a ‘toasty’ overtone. Barley tea being weak and needing a longer steep than most other teas means that it is ideal for mixing, and the risk of ruining the initial flavour of the tea is minimal.

I’ve also tried a barley blend [specs], which had other grains such as rice as well. It was very tasty, the rice made the tea taste thicker while still retaining the barley flavour.

Fruits

Citrus Fruits and Peel

Gives the water a zangy flavour. I wouldn’t recommend using the insides of the fruit. Opt for the peel instead, which not only keeps way longer (after drying), but doesn’t contain a lot of acid that gives a bad aftertaste. If you really want to use the insides, boil them in water for a while first, which will weaken the taste (the water used to boil these also tastes good if drank alone).

Pineapple

Way too sour and leaves an acidic aftertaste that is quite unpleasant for the tongue. I would strongly suggest using lemon, orange, or tangerine if you want a tangy flavour. I tried making a blending pineapple with some Anji tea, hoping that maybe the deep rich flavour of the tea would mask out the acidicness, but it proved to be of no avail, the acidic taste completely cut through the tea and wrecked the flavour.

Rose Water

I’ve tried water from dried roses grown from my garden. To me, pure rose water has a weak bittersweet aroma, and drinking it interposes a whimsical feeling, perhaps because roses are associated with airy ideals like romance. Blending it with any tea masks the subtler flavours and replaces them with a floral taste.

Appendix: Thoughts on Teaware, Water, and Materials

A Digression on Brewing Conditions

Temperature

Increased temperatures seem to result in a linear proportional increase in dissolved components extracted from tea given other conditions are constant. A couple things of note:

Most Chinese, including well known tea masters do not care for water temperature and brew all their teas at full boiling. It is possible to control other parameters besides temperature to get similar results as changing the temperature itself.
Consistent results with water temperature is a pain to manage if you really want to be precise with it, and will vary slightly with different conditions and teaware. For example, see An Aside About Kettles.
Temperature has less of a pronounced effect the shorter the brewing time is. Or said differently, longer brewing time amplifies differences in temperature. In particular, some studies show that there is no significant difference on tea steeped with different temperatures when the steep time is less than one minute. This will be of particular interest to gong-fu steepers (very short steep time) and grandpa-style steepers (very long steep time).

An Aside About Kettles

tldr; Most modern electric kettles are startlingly inaccurate in the thermal realm, and it’s pretty easy to see why once you think about it a little. However, if you are brewing water to full boiling, this doesn’t actually matter.

Maintaining water at a temperature as dramatically different as near boiling while surrounded by atmospheric conditions is non trivial. If you have an kettle with an electric thermometer, they are typically programmed in a rudimentary way to heat to the desired temperature and then turn off the heating element. This will produce inaccurate results because the heating element will still be hotter than the water when it is shut off! This will mean that the water will actually be hotter than you intended. This is not actually a problem when the water is heated to 100^oC because that is the ceiling for water temperature while in liquid state (if you heat it up further, the energy will go into making the water gaseous rather than changing the temperature). The problem is when you want a temperature cooler than 100^oC. If you get a good quality kettle, it will be properly programmed based on the amount of water to stop some time before the requested temperature, or to hold at the requested temperature at the end for a while to wait for it to stabilize.

That’s if you are fortunate enough to own a kettle with an electric thermometer. Most of the kettles on the market today automatically turn off using either a pressure switch or a bimetallic mechanism, both of which are exceedingly inaccurate and inconsistent. In the case of the pressure switch, the kettle turns off when there is enough steam pressure to pass through a vent triggering a pressure switch. These are not very accurate, and don’t make much sense either as they depend too much on how full the kettle is. The higher the water level, the less room for steam and by the Ideal Gas Law volume and pressure are inversely proportional, meaning that the less water you put in, the more time the kettle will stay on. Not what we want (in fact, we want precisely the opposite).

The bimetallic spring mechanisms works by using hot steam to heat up a metal strip, causing it to bend due to expansion, eventually cutting the power when it gets hot enough. If your kettle makes a clicking sound when it cools (coming from the metal strip returning to it’s normal, cooled position), then this is the type of kettle you have. Because this mechanism uses the temperature of the air rather than the water, these are subject to similar limitations as the steam pressure switch. Volume differences result in a large amount of variability, and even given perfect transduction conditions, bimetallic strips are not very accurate in their own right.

A Digression on Teapots

Hardcore tea enthusiasts will say that teapot effects taste. This is not exactly wrong (Anything that touches the tea will effect the taste. This is true even of chemically inert substances like glass, because the shape of a teapot effects the brew perhaps even more tangibly than the teapot materials because it will effect the way in which the leaves spread and how much they are allowed to spread.), but whether or not it actually matters to you depends on various things:

Does the teapot matter to the average Western style brewer? Probably not much in terms of shape. In terms of material, maybe, but most likely not.

When brewing Western style, with the low leaf to water ratio, the tea leaves will have room to completely spread as long as you aren’t using a really small teapot or one of those tiny ball strainers (in which case you should stop using them). You will get similar results with any shape of pot if the leaves are allowed to expand fully and flow through the water in a reasonably free manner. The material may matter if we are comparing something like purple Yixing clay with glass, though if you have a Yixing pot I would be questioning why you are using Western style brewing in the first place.

Does this matter to a gong fu brewer or others using a high leaf to water ratio? Definitely matters in terms of shape. In terms of material, maybe, but only for a certain alcove of brewers using soft clay pots that have been specifically seasoned.

When using a high leaf to water ratio, the amount the leaves can expand will be largely dictated by the teapot. Any experienced brewer in this style will know that wet tea leaves have a surprisingly high amount of friction. A large clump of leaves in one area will stay as a clump even when water is poured through it. This is more true of large tea leaves than small ones, but most gong fu brewers are going to be drinking larger, darker teas that have been picked later anyways. Tea clumping together leads to less surface area and water flow which leads to subduing of the flavour. It also leads to different areas of the pot having differing tastes. Some brewers even discard tea from certain areas of the pot they claim undesirable.
As for the material, soft clay pots like Yixing that are seasoned with tea of specific types will effect the taste because the pot will retain flavour from these. You can check this by simply tasting plain water that has been poured into a heavily used Yixing pot. The plain water will be flavoured by the previous tea infusions. However, this only matters when you brew the pot with teas of slightly differing qualities. As you can imagine, brewing the same tea with a Yixing pot which has only brewed the same tea before won’t change the flavour a whole lot, because it’s the same tea.

Don’t other aspects of the teapot besides shape and material influence taste? What about airspace, heat retention, spout size, pour time…?

Probably doesn’t influence the actual tea in tangible ways. However, it can influence the experience, which can influence taste indirectly. Eg: teapots with higher heat retention like large cast iron ones will make hotter tea, and the human tongue is less sensitive to taste at the ends of the heat spectrum when tasting extremely hot or cold things, so it may mask flavours like bitterness.

What about teacups?

In terms of directly influencing taste, its effects will be similar to materials discussed above. Inert teacup materials will not influence taste compared to tea directly from the pot, save for taste perception changes due to temperature variance. Cups made from porous clay may if it was seasoned for different teas in the past.
However, the “experience” aspect does play a large factor in indirectly influencing taste. The feel of the cup, the thickness, weight, size in your hand, etc. will effect your perceptions of the tea inside, and plays a surprisingly large role in dictating taste. Further reading:
- Yang, S.-C., Peng, L.-H., & Hsu, L.-C. (2019). The Influence of Teacup Shape on the Cognitive Perception of Tea, and the Sustainability Value of the Aesthetic and Practical Design of a Teacup.
- Li, X., Qi, Y., Spence, C., & Wan, X. (2019). Influence of teaware on subjective ratings of, and taste expectations concerning, tea.
- And many more… Not only tea. There are many studies on effect of physical characteristics on perception of sensory stimuli like taste, sound, lighting, etc.
Another factor to consider is aroma. A teacup allowing more airflow over the tea will dissipate the aroma of the tea faster than a narrower, more constricted cup. Aroma obviously has a large influence on taste.

A Digression on Brewing Methods

Is there a tasteable difference in tea brewed with different brewing styles?

In general: Yes, especially for lighter teas. However, please do note that in niche hobbies (eg: tea, mechanical keyboards, audiophilia, fountain pens, etc.), individuals will exaggerate even the smallest differences because as a community becomes more specialized, their focus becomes narrower and standards and sensitivity to changes increase. This is a good point to keep in mind when reading tea reviews and buying tea as well :)

Does brewing covered vs uncovered have a tangible effect on taste?

Most likely only for long periods of time. I can see two concrete factors at play here: Effecting oxygen content and effecting water temperature. On oxygen content see A Digression on Dissolved O₂. On water temperature, it is highly variable with brewing style. Consistent with what I have said before, brewing style will have a much larger effect, and with even minimal skill you will almost certainly be able to override any temperature induced effects that directly come from the pot by changing brewing parameters like time, technique, and leaf to water ratio. And adjusting brewing parameters are much more flexible than relying on things like the physical pot.

A Digression on Dissolved O₂

The water I use to make tea comes from a Zojirushi electric boiler that keeps water at temperature you can set. This allows me a constant supply of heated water for tea at any time. Many tea fanatics only use freshly boiled water, arguing that water left at high temperatures for long periods or boiled twice results in a low amount of dissolved oxygen which will lead to worse tasting tea. I ran a few rounds of blind trials with various teas to test this, and I was not able to taste a difference. But this is not definitive proof, thus I tried to quantify the maximum amount of dissolve O₂ that water could hold as the temperature increases.

Our goal: Find a close theoretical approximation of oxygen content and temperature. Then explain why this doesn’t actually matter.

We can calculate the solubility of oxygen at SATP (25^oC and 100 kPa), with Henry’s Law, assuming that the percentage of O₂ in dry air is 21% (the commonly accepted quantity), and a molarity-based Henry’s Law constant ( $H^{cp} = \frac{c_{aq}}{p}$ , that is, the molar concentration over the partial pressure) of $1.26 \times 10^{-3} \frac{\text{mol}}{\text{L} \cdot \text{atm}}$ (Warneck & Williams 2012 ¹):

$\begin{align*}S_{\text{O}_{2}}^{25^o C} & = 1.26 \times 10^{-3} \; mol/(L \cdot atm) \times 0.21 \; atm \\ & = 2.65 \times 10^{-4} \; mol/L \end{align*}$

This is about consistent with commonly accepted values. If we wanted, we can convert this to a more intuitive measurement of mg/L by using the molar mass of O₂ (32.00 g/mol):

$\begin{align*}2.65 \times 10^{-4} \; mol/L \times 32.00 \; g/mol &= 8.47 \times 10^{-3} \; g/L \\ &= 8.47 \; mg/L\end{align*}$

Already, we can see that completely pure water at room temperature can only hold 8.47 mg per litre of oxygen. This is a small amount, O₂ being a medium-sized, double bonded, non-polar molecule, is not actually very soluble in water. Additionally, this number will decrease if the water has other compounds dissolved like minerals and such, and we haven’t even begun to increase the temperature yet.

A relationship between temperature and the value of Henry’s “constant” can be described with the Van ’t Hoff equation, though it assumes the enthalpy of solution is constant when in reality it also changes with temperature. Thus, it is only suitable for a limited temperature range where the enthalpy of solution changes by an insignificant degree, around 20 K is a reasonable amount. As we want to find the change from room temperature water (298.15 K) to boiling water (373.15 K), this method will probably not provide precisely accurate results, and additionally it assumes we are dissolving an ideal gas, but it will give a general sense of how O₂ solubility changes with temperature. Here is the Van ’t Hoff expression for temperature dependence on Henry’s law constant:

$\frac{d\; \ln H}{d\;(1/T)} = \frac{-\Delta_{sol} Enth}{R}$

where $T$ is temperature, $R$ is the ideal gas constant, and $\Delta_{sol} Enth$ is the enthalpy of solution (in our case, for oxygen in water). I use $Enth$ instead of the commonly used $H$ for enthalpy to avoid confusion with Henry’s constant.

And here is a usable equation for estimating $H$ with change in $T$ . See fn² for the complete derivation.

$H(T) = H^{\circ }\exp\left[\frac{-\Delta_{sol}Enth}{R}\left(\frac{1}{T} - \frac{1}{T^{\circ}}\right)\right]$

Using this equation, here are the estimations I made for Henry’s constant and the O₂ solubility. We assume that $\frac{d \ln H}{d (1/T)} = 1700$ (Warneck and Williams 2012¹), which seems to be the most reliable number as of now. The ‘[SATP reference]’ which was calculated above is used as the reference $H^{\circ}$ and $T^{\circ}$ values.

Table 1: Estimations of the value of Henry's Constant (H^cp) and the estimated O₂ solubility at equilibrium for different temperatures

Temperature	Estimated $H^{cp}$ value $mol/(L\cdot atm)$	Estimated O₂ Solubility
273.15 K / 0^oC (Freezing point)	2.12 x 10^-3	4.46 x 10^-4 mol/L — 14.3 mg/L
294.15 K / 21^oC (Avg room temp)	1.36 x 10^-3	2.86 x 10^-4 mol/L — 9.15 mg/L
298.15 K / 25^oC [SATP reference]	1.26 x 10^-3 (measured)	2.65 x 10^-4 mol/L — 8.47 mg/L
323.15 K / 50^oC	8.11 x 10^-4	1.70 x 10^-4 mol/L — 5.45 mg/L
353.15 K / 80^oC	5.18 x 10^-4	1.09 x 10^-4 mol/L — 3.48 mg/L
358.15 K / 85^oC	4.85 x 10^-4	1.02 x 10^-4 mol/L — 3.26 mg/L
363.15 K / 90^oC	4.54 x 10^-4	9.54 x 10^-5 mol/L — 3.05 mg/L
368.15 K / 95^oC	4.26 x 10^-4	8.95 x 10^-5 mol/L — 2.86 mg/L
373.15 K / 100^oC (Boiling point)	4.01 x 10^-4	8.41 x 10^-5 mol/L — 2.69 mg/L

For the most part, this looks very reasonable, and at lower temperatures (under 50^oC) seem quite accurate when compared to the IUPAC ones after they are converted and corrected for the units and partial pressure values we used. Our values are also comparable to the ones in the Wikipedia solubility table. I’m not sure about the accuracy of the higher values, but it’s highly likely that there is a fair amount of error space, not only because of the differing enthalpy of solution for differing temperatures of water, but also because the water will start steaming at around 80^oC, meaning the air above the water will be H₂O saturated. Water vapour saturated air holds less O₂ than dry air, about 20.3% O₂, a 0.7% difference from the value we used (21%). Thus, we can expect a minimum error of around ± 3.3%, assuming that the air is fully saturated at 100^oC. It is likely that this number is closer to ± 5% or even higher if we factor in the solution enthalpy error and measurement errors, as well as the fact that O₂ isn’t an ideal gas. Even so, looking at the data it is still very reasonable to think that temperatures above 90^oC probably won’t be able to hold more than a maximum 3 mg/L of dissolved O₂, and that’s the high ceiling at sea level and with 100% pure water.

Of course, this is the level for the system at equilibrium. If the water has just been raised to a high temperature very quickly, it is possible that larger amount of oxygen could still be dissolved, but will quickly dissipate after a short period of time. While this could have an effect on tea, it has too many variables to quantify, and is hard to measure (probably why there are few studies on rate of solution of oxygen). Here are some things to consider that effect the rate of solution (excluding temperature) from the perspective of making tea:

Agitation of the water. In general, water that is more disturbed will reach equilibrium with O₂ in the atmosphere faster, until a certain point where more disturbance doesn’t decrease or increase the time taken (Downing & Truesdale, 2007).
Shape of the container. The more surface area the water is exposed to, the faster equilibrium will be reached, eg: If you are brewing tea with a mug that has a wider opening. The shape of the container also determines the convection currents that stir the water (due to water cooling at the top and sinking due to density), which will have an effect on how quickly oxygen can dissolve.

In conclusion, for heavier varieties of teas like black tea, it is highly likely that other factors namely steep time and method, are much more influential to the taste than the dissolved O₂ content. Even for delicate teas with very complex and fragile chemical interactions (like green or white tea), I would be hard pressed to think that the average drinker would be able to tell the difference in a blind trial, I certainly couldn’t when I did a test. Especially since we are talking very low amounts of oxygen (<3 mg/L).

A fairly reliable reference book used for values relating to Henry’s Law in this article. The Atmospheric Chemist’s Companion. scihub link (cough, cough) ↩︎
[Note: ‘’ is used to denote enthalpy rather than to avoid confusion with Henry’s constant]

Writing out the chemical formula for dissolving of oxygen in water (O₂ is used as an example because we are discussing it, this could be applicable to any gas, though). The change in enthalpy will be equal to the enthalpy of solution for the gas in water:
$O_{2\;(g)} \rightleftharpoons O_{2\;(aq)} \tag{$\Delta Enth = \Delta_{sol} Enth$}$
Writing the equilibrium constant expression for this:
$K = \frac{\gamma \cdot [g]}{\eta \cdot [aq]}$
- Where and are the concentrations of each species at equilibrium, and γ and η are activity coefficients.
For our purposes, we can define Henry’s constant for a substance as follows:
$H = \gamma^{inf} \cdot p^{sat}$
- Where $\gamma^{inf}$ is the infinite dilution value for the activity coefficient of the solute inside the solvent, and $p^{sat}$ is the vapour pressure of pure solute for our given temperature (in our case above, since air is not 100% oxygen, we use the partial pressure). Because both sides of the equation are equal, we can thus make the following ratio where $T_{1}$ and $T_{2}$ are two absolute temperatures:
  $\frac{H(T_1)}{H(T_2)} = \frac{\gamma^{inf}(T_1) \cdot p^{sat}(T_1)}{\gamma^{inf}(T_2) \cdot p^{sat}(T_2)}$
If we assume that and are close, using our equilibrium constant expression from above, we can extend to a ratio of equilibrium constants:
$\frac{H(T_1)}{H(T_2)} = \frac{\gamma^{inf}(T_1) \cdot p^{sat}(T_1)}{\gamma^{inf}(T_2) \cdot p^{sat}(T_2)} \approx \frac{\frac{\gamma(T_1) \cdot [g](T_1)}{\eta(T_1) \cdot [aq](T_1)}}{\frac{\gamma(T_2) \cdot [g](T_2)}{\gamma(T_2) \cdot [aq](T_2)}} = \frac{K(T_1)}{K(T_2)}$
This is true because if we assume that only the ratio of pressures matter, then we can cancel out the [aq] parts, and we are left with a ratio of the concentration of the gas, analagous to the ratio of the (partial) pressures, which will be the same as the ratio of Henry’s constants:
$\frac{\frac{\gamma(T_1) \cdot [g](T_1)}{\eta(T_1) \cdot [aq](T_1)}}{\frac{\gamma(T_2) \cdot [g](T_2)}{\gamma(T_2) \cdot [aq](T_2)}} = \frac{\gamma(T_1) \cdot [g](T_1)}{\cancel{\eta(T_1) \cdot [aq](T_1)}}\times \frac{\cancel{\gamma(T_2) \cdot [aq](T_2)}}{\gamma(T_2) \cdot [g](T_2)} = \frac{\gamma(T_1) \cdot [g](T_1)}{\gamma(T_2) \cdot [g](T_2)} = \frac{\gamma^{inf}(T_1) \cdot p^{sat}(T_1)}{\gamma^{inf}(T_2) \cdot p^{sat}(T_2)}$
In other words, we can assume the following relationship:
$\frac{H(T_1)}{H(T_2)} \approx \frac{K(T_1)}{K(T_2)}$
Thus we can use the Van’t Hoff equation (rewritten in a convenient way for this purpose), with the enthalpy of solution :
$\frac{d \ln K_{eq}}{d(1/T)} = -\frac{\Delta_r Enth}{R} = -\frac{\Delta_{sol} Enth}{R}$
And then taking the definite integral of the above between and , and solving for $K_{1}$ :
$\begin{align*}\ln \frac{K_1}{K_2} &= \frac{\Delta_{sol} Enth}{R}\left(\frac{1}{T_1} - \frac{1}{T_2}\right) \\ K_1 &= K_2 \exp{\left[\frac{\Delta_{sol} Enth}{R}\left(\frac{1}{T_1} - \frac{1}{T_2}\right)\right]} \end{align*}$
Replacing and with and :
$H(T_1) = H(T_2) \exp{\left[\frac{\Delta_{sol} Enth}{R}\left(\frac{1}{T_1} - \frac{1}{T_2}\right)\right]}$
We have our equation. Now as long as we have a known measure of Henry’s constant for one temperature , we can use this to estimate Henry’s constant at another temperature . To make this more intuitive, we can replace and it’s Henry’s constant value with $T^{\circ}$ and $H^{\circ}$ , and get rid of the numbering:
$H(T) = H^{\circ} \exp{\left[\frac{\Delta_{sol} Enth}{R}\left(\frac{1}{T} - \frac{1}{T^{\circ}}\right)\right]}$
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