Jul 5, 2016

The Eight Basic Tastes or Flavors

Last month, I delivered a talk at one of our local libraries - in Whitefish Bay - straying a bit from philosophy into the field of gastronomy (you can watch the video of the talk here).  This isn't an area in which I do all that much work, but in which I've got a considerable, though basically amateur, interest.  The topic that I proposed is one that has exerted a kind of distracting pull upon my research work for some time - a history of basic tastes or flavors of food.

At present, and for roughly the last century and a half, most people here in the West tend to think that there are four main flavors - sometimes five, counting the umami flavor, what we might call an intellectual import from Japanese researchers.  There are, to be sure, food researchers here in the West who do discuss and research other basic tastes or flavors - but the additional gustatory qualities they rightly bring to light are typically regarded as recent additions to an otherwise all-too-simply palette of the palate.

Talk about additional flavors beyond the four or five typically acknowledged and taught about here in the West, and a common first response from other people is to reference the basic tastes distinguished in other culinary traditions of great civilizations of the East - in Indian or Chinese cooking, for example.  And yet, here in the West, there is also a millennia-old tradition of thinking in terms of significantly more than four flavors, one that tends to be overlooked.  It reaches an early apex and touchstone in several passages from Aristotle's works, in which he sets out for us the eight basic flavors.

Early Greek Classifications of the Flavors

It is unfortunate we possess such a small proportion of the body of writings from ancient Greek and Latin sources.  It is doubly unfortunate - but for a number of reasons, completely understandable - that we possess only a fragmentary set of references to the hard-earned conceptions worked out within the culinary arts in the course of their early development.  We do have a number of interesting, though often all too allusive descriptions of practices of eating, drinking, entertaining, feasting, cooking, preparation, even farming, but we lack any systematic discussions of flavor on the part of those who actually cooked the food, created or perfected dishes, or who ordered the courses of meals.

Where discussions of the flavors do occur, in the literature that we do still possess, is in medical and philosophical works.  Greek medicine focused significantly upon diet, and naturally explored the nexus between food, flavor, and what were conceived to be the basic elements of the body. Philosophers were quite interested in how sensation worked, but unfortunately for us, were considerably less interested in taste than they were in certain of the other senses.  Still, though, they did devote some attention to distinguishing what the fundamental or basic flavors sensed by taste were, and what implications they might have for the body itself and its various processes, or for the nature of different foodstuffs.

Democritus of Abdera (roughly 460-370 BCE) apparently gave the matter some thought, as we know from Aristotle and from Theophrastus (Aristotle's friend, student, and successor, who became the scholarch of Aristotle's Lyceum after his death).  It is not clear precisely what flavors he did set out as basic or fundamental, but we can safely say that, in line with his materialist and specifically atomist theory, Democritus did think that the different flavors exhibited their qualities for sensation because of the varied shapes of the particles that caused the sensation of flavor.

His contemporary, Hippocrates (also roughly 460-370 BCE) references flavors in his own writings, particularly in On Ancient Medicine, a summary and critique of the discipline in Greece up to his own times.  I'll just mention two particularly interesting points about his treatment.  The first is that he stresses that food particularly extreme in taste, i.e. that is very sweet, very salty, or very bitter, is likely to prove unhealthy.  The second is that he explicitly distinguishes six flavors - in addition to sweet, sour, salty, and bitter, there is also the astringent (struphnon) and the insipid (pladeron).

In one of his later dialogues, the Timaeus, Plato (c. 429/423 – 348/347 BCE) provides a discussion bearing upon taste and the tongue, in which he distinguishes seven flavors:
. . . for whenever earthy particles enter into the small veins which are the testing of the tongue, reaching to the heart, and fall upon the moist, delicate portions of flesh, when, as they are dissolved, they contract and dry up the little veins, they are astringent if they are rougher, but if not so rough, then only harsh. Those of them which are of an abstergent nature, and purge the whole surface of the tongue, if they do it in excess, and so encroach as to consume some part of the flesh itself, like potash and soda, are all termed bitter. But the particles which are deficient in the alkaline quality, and which cleanse only moderately, are called salt, and having no bitterness or roughness, are regarded as rather agreeable than otherwise. Bodies which share in and are made smooth by the heat of the mouth, and which are inflamed, and again in turn inflame that which heats them, and which are so light that they are carried upwards to the sensations of the head, and cut all that comes in their way, by reason of these qualities in them, are all termed pungent. But when these same particles, refined by putrefaction, enter into the narrow veins, and are duly proportioned to the particles of earth and air which are there, they set them whirling about one another, and while they are in a whirl cause them to dash against and enter into one another, and so form hollows surrounding the particles that enter, which watery vessels of air (for a film of moisture, sometimes earthy, sometimes pure, is spread around the air) are hollow spheres of water; and those of them which are pure, are transparent, and are called bubbles, while those composed of the earthy liquid, which is in a state of general agitation and effervescence, are said to boil or ferment, of all these affections the cause is termed acid. And there is the opposite affection arising from an opposite cause, when the mass of entering particles, immersed in the moisture of the mouth, is congenial to the tongue, and smooths and oils over the roughness, and relaxes the parts which are unnaturally contracted, and contracts the parts which are relaxed, and disposes them all according to their nature, that sort of remedy of violent affections is pleasant and agreeable to every man, and has the name sweet.
Notice that the insipid flavor referenced by Hippocrates is not present in this Platonic passage, but that there are two additional flavors introduced - the rough (austeron) and the pungent (drimu).

It seems quite unlikely that these thinkers engaged in any sort of invention of basic flavor profiles.  Their innovations - which were many - occur in many other modalities.  Rather, we should see these flavor terms as reflective of commonly distinguished, though perhaps not well-understood, tastes in their contemporary culture and civilization.


Aristotle's Definitive Treatment of the Flavors

The discussion of the flavors that would come to be fairly normative, certainly the most influential, in the Western (and Islamic) gastronomic traditions from antiquity on, derives from two of the texts of Aristotle (382-322 BCE).  In On the Soul, he explicitly identifies eight flavors as basic.  In On Sense and the Sensible, he admittedly attempts to reduce these to seven, but does so by somewhat implausibly trying to claim that two flavors can be assimilated to each other.  I should point out as well that Aristotle also discusses a number of interesting aspects of flavor and food in the lesser known work, the Physical Problems.

In book 2 of On the Soul, Aristotle writes:
The species of flavor are, as in the case of colour, simple, i.e. the two contraries, the sweet and the bitter, and secondary, that is, on the side of the sweet, the oily, on the side of the bitter, the salty, between these come the pungent, the rough, the astringent, and the sour; these pretty well exhaust the varieties of flavor. It follows that what has the power of tasting is what is potentially of that kind, and that what is tasteable is what has the power of making it actually what it itself already is.
Notice that the tastes or flavors can be set out on a kind of continuum, with sweet (gluku) at one end and bitter (pikron) on the other end.  All of the other flavors fall in between, somewhere along this continuum.  This suggests the possibility of something analogous to a scale of musical notes or of colors, a correspondence Aristotle will find rather seductive in On Sense and the Sensible:
As the intermediate colors arise from the mixture of white and black, so the intermediate flavors arise from the sweet and bitter; and these flavors too, severally involve either a definite ratio, or else an indefinite relation of degree, between their components, either having certain integral numbers at the basis of their mixture, and, consequently, of their stimulative effect, or else being mixed in proportions not arithmetically expressible. The tastes which give pleasure in their combination are those which have their components joined in a definite ratio. 
The sweet taste alone is oily, (therefore the latter may be regarded as a variety of the former), while (so far as both imply privation of the sweet) the salty is fairly identical with the bitter. Between the extremes of sweet and bitter come the rough, the pungent, the astringent, and the sour. 
Flavors and colors, it will be observed, contain respectively about the same number of species. For there are seven species of each, if, as is reasonable, we regard grey as a variety of black (for the alternative is that yellow should be classed with white, as oily with sweet); while red, violet, green, and blue, come between white and black, and from these all others are derived by mixture. Again, as black is a privation of white in the translucent, so salty or bitter is a privation of sweet in the nutrient moist. This explains why the ash of all burnt things is bitter; for the potable (the sweet) moisture has been exuded from them.
Shoehorning the eight flavors into a schema of seven isn't all that successful, especially given that, as Aristotle notes, we might do that in two different ways - subsuming the oily into the sweet, or the salty into the bitter - and even more so since he, and the wider culture he belongs to, has already differentiated these various flavors.

What Are These Various Flavors?

If you watch the video of the talk, you'll notice that a good portion of it was devoted to a tasting component - which I should note, was quite successful, and was very well-organized by my wife and children, who planned the tasting, assembled all the components, and doled them out for the participants.  When discussing food, and especially flavor, it can be invaluable to have a set of common sensory, experiential reference points to draw upon.

Some of the tastes or flavors - precisely because of the predominance of the four-flavor schema in our contemporary thinking and teaching about food - might be a bit difficult to make sense of at first.  What does it mean to be "pungent"?  Or "rough"?  Fortunately, we possess a number of useful examples, comparisons, and descriptions stemming from ancient texts, including a number of references which Aristotle himself drops in his works.  It would be excellent if we had more of them, but we certainly have enough to tie each of these flavors into a basic flavor, and to find contemporary examples of them for audiences of the present.

Let's discuss then each of these eight tastes briefly, so that there isn't any lingering confusion about what they extend to, are embodied, in, or include.

Sweet is straightforward enough.  The Greek term for this is glukus, and we are provided with all sorts of useful examples by ancient authors, honey being the most paradigmatic one.  For the talk, we used honey, fig, and date as examples.

Oily is one English translation of the Greek liparon, which can also be expressed by "fatty," or "rich." Olive oil is one common example, not only in ancient times, but also for our tasting.

Pungent is one way in which the Greek drimu can be rendered.  "Spicy" or even "Piquant" can work as well.  One classic example for this is pepper, though that is a bit later.  Aristotle mentions the herb thyme.  We used a peppercorn and mustard.

Astringent is the most common translation in the food literature for the Greek struphnon.  Think unripe pears (or if you've got them, quince).  Aristotle also uses acorns as an example. This sort of flavor causes you to pucker, but is not acidicly sour.  For the tasting, we used pomegranate juice, though cranberry also has this property.

Rough is one of the more difficult to translate terms, corresponding to the Greek austeron.  Think of the dryness of dry wine produced by tannins, and you're on the right track.  For the tasting, we used walnuts and black tea to convey this taste.

Sour is one that we are familiar with, and is a rendering of the Greek oxu, which can also be expressed by "acidic".  The Greeks tended to bring up vinegar as a paradigm, and we played off of this by supplying the participants with vinegar potato chips, supplementing them with a lemon wedge.

Salty is another taste we are familiar with, the translation of halmuron, and not surprisingly, the classic example was indeed salt.  We used kosher salt, with its larger grain than standard table salt, for that quality.

Bitter too is a taste we are all familiar with.  The Greeks, who called it pikron, provided a wealth of examples of the bitter, including ashes!  We used the relatively bitter vegetable kale for our example.

A Short and Selective History of Flavors After Aristotle

Aristotle's student, Theophrastus (371 – c. 287 BCE) apparently wrote a work in five books (that is, chapters, contained in scrolls), called Peri Khulon, or On Flavors.  Regrettably, it is one of the many classic sources lost to us, but it also does not appear to have exerted much influence upon writers much closer to Theophrastus in time.   He does, however, tell us a good bit more about flavors in his works focused upon plants.

The medical writer, Galen (200/216 CE) is another important early source on flavor.  Conversant with earlier classic writers, including Aristotle and Theophrastus, he not only recognized a sizable multiplicity of basic flavors, but even tried to reduce certain of the flavors to variations of others.

Christian thinkers like Nemesius (4th-5th century CE) and John Damscene (675/676 – 749 CE), without expanding much upon the examples, descriptions, or workings of them recognize the eight tastes discussed by Aristotle.  It seems that for them, this was a matter of common knowledge.

There are also authors who end up commenting upon one or both of Aristotle's two works that provide classifications of flavors - the On the Soul, and On Sense and the Sensible.   John Philoponus (490 – c. 570), for example, will write a commentary on the former, and provide us useful examples of each of the flavors.

In the Islamic world, Ibn Sayyar al-Warraq (900s CE) writes a famous Cookbook (Kitāb al-Ţabīkh), employing the eight flavors.  The philosopher - or, if you like polymath - Ibn Sina (980 – 1037 CE) also uses the eight flavors, and discusses, among other things, their physical effects and uses in medicine.

The story of the eight (or, in some cases, even more!) basic flavors goes on and on, encompassing many other thinkers both in the West and in the flourishing continent-spanning Islamic civilization of the Middle Ages.  It continues on through the Renaissance and well into the Modern Period.  So, what happened?  How did we end up with only four, or perhaps five, basic flavors as the norm? That's another chapter in the story, which for now, I end right here.