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The obvious answer would be of course not, that the two things are completely different. Astringency can be mistaken for bitterness, but they're different.

Then lately I've been considering how paired forms of mineral taste and certain feel aspects tend to couple, if it couldn't be the case that some forms of feel could naturally affect taste interpretation, beyond this error theory. It's probably nothing, just overthinking patterns. What do you think?

Descriptions like 'chaulk', 'rind', 'stems' immediately come to mind

I don't think that humans can divorce flavours or tastes from the sensations that accompany them as a matter of ordinary human experience.

The concept of 'minerality' got its own special mention around here a while ago...

Andrew

This is a complicated question without a clear answer, because it depends on:

• The genetics of the Individual

• The Tea

• The Environment

Astringency is a trigeminal sensation, which means it is perceived through a different nerve pathway from olfaction (aroma), gustation (flavor), and somatosensory attributes (heat, cold, pressure, etc); which creates three complications:
1) the source of the sensation (tannins, caffeine, etc)
2) the cross modality of sensation
3) the individual

Starting from the top, 1) a stimuli is not limited to a single response, and thus a compound can exhibit more than one flavor attribute (such as bitter and astringency). Certain co-responses are more common than others, leading to a perceptual effect called adaptation - a learned response to a stimuli (for example: in the USA, cinnamon is predominately paired with sweet things, and thus the presence of cinnamon creates the perception of sweetness even when no sweet compounds are present for a high proportion of the population).

2) While in theory an independent signal could be carried along a nerve pathway, in practice these nerve and neural pathways are not independent - they interact with each other in various ways. This is called the cross modality of perception, and it is far more extensive than most people understand. For example, did you know that loud music in a bar makes you prefer stronger flavors, even if you don't prefer those specific flavors? (which means its a general effect). Or for example, that high pitch sounds in the environment increase the perception of sweet aromas? This level of interaction happens between different perceptions (sight, sound, olfaction, etc) and also happens within a sensation - so the presence of astringency, can, in certain circumstances, increase the perception of other unrelated flavors (such as bitterness).

Finally, 3) all of the above is predicated on the genetics of the individual, which controls the perceptual phenotype of the individual. While some individuals might perceive some compounds as astringent - others won't.


Thus, in conclusion: astringency and bitterness are different sensations that follow different nerve and neural pathway. Astringency and bitterness are common co-responses to the same stimuli, more often found together than apart, leading to adaptation such that the presence of one increase the perception of the other even when its not there. Astringency, which follows the trigeminal nerve is one of the least genetically diverse sensations; bitterness which follows multiple nerves is the single most genetically diverse perception.


Source: I do this professionally to develop better tasting products.

Great post @akedomakona, thanks! I believe astringency in tea might be of different importance to different people and their "taste interpretation". Some tolerate high amounts, others avoid it, to the point of trading off a lot of flavor. For me, at some point, high astringency tends to flatten everything else, so instead of flavors getting deeper and more complex with higher extraction, they get lost. I think this should be similar for everybody, though the exact level probably varies a lot due to genetics and habit/conditioning. On the other hand, I've noticed I also belong to a rarer group that *need* a minimum level of astringency to interpret some tastes favorably, incl. tea. This could be some form of adaptation (I guess astringency indicating freshness/intact natural preservatives) that's not been of great benefit for millennia, so not really selected for. In any case, for me personally, a small amount of astringency could be the difference between a bouquet I lose myself in and one that is interesting but "missing something" and not really taking off for me.

Great reply @akedomakona

That's pretty much a detailed extension of what one ordinarily experiences, just going a bit further in terms of detail and explanation. It's interesting how acclimation plays into all that, preference shift, and what one tends to pick up.

@teatray Thanks! You're generally correct - my answer was only about perception and entirely ignores preference.

Generally - bitterness (not astringency) has become an increasing preference amongst educated upper-class individuals with high levels of exposure to the contemporary shifts in culinary and packaged foods; as products have become less sweet and trends such as "low sugar", "low sodium', "natural flavors", "organic", etc have taken hold, products of "higher quality" (read: more expensive) have become more bitter. (This is not true for astringency generally, though it could be true in a specific category, such as pu'er or green tea)

In any case, the acquisition of preference is predominately independent from the genetics of perception.

I wrote more about this here (note, pay-walled): A Bourdieu’dian Analysis for the Construction of an Education in Tea

@akedomakona

Would be nice if you opened a thread focused on this mythical creature called "sweetness" applied to tea.

As much as i've chased this particular unicorn and even after going through conceptual mashups like the one from Teavivre or the sources suggested at the Wikithing plus challenging myself over these past few years plus taking into account that "sweetness" isn't perceived the same way on the west... the closest i've been was this ghost called "oral illusion".

At this point in time might be the lone item within the tea realm i've never experienced when it comes to notes or different feelings and certainly would appreciate additional points of view that could certanily stem from your opening statement on this subject.