JOHN THE OBSCURE ™
By John Ruch
© 2005
Please Pass the Umami,
And Can I Get Some Kokumi on That?
It began with a July 25 Associated Press article about research indicating that cats can’t taste sweet.
Down at the bottom of the story it was dryly reported that there are “five major taste sensations: salty, sour, sweet, bitter and umami, the taste of the food additive MSG and fermented soy products, among other foods.”
Umami?!
I did the double-take. I reflexively checked my head for wounds. I mentally inventoried myself for signs of drugging or delirium.
Then I had to wonder how I could possibly have missed a scientific breakthrough as significant as adding a fifth “basic taste,” as it is known colloquially—let alone one with such a wild, New Age name. And one that happened apparently so long ago that AP doesn’t feel the need to treat it as a surprise. The story might as well have said dragons had proven to be real and were in 10 major zoos around the country.
Of course, the AP was just engaging in slavish, gullible reporting as the major media are wont to do. It turns out the umami debate is a rich banquet of cultural forces ranging from hard science to Asian exoticism, and from attempts both to widen traditionally narrow descriptions of taste and to market the bad-reputation food additive monosodium glutamate (MSG) as something safely natural. Dinner guests include neurologists and psychologists, skeptical of each other’s fields as always.
And there is a debate. There’s little doubt that there is a kind of umami flavor; whether it’s a “basic taste,” and whether that term actually means anything, are far less clear.
It’s such a weird, ethereal controversy that, on the one hand, I can tell you definitively that I have tasted umami; on the other hand, I did it in a way the MSG industry says is impossible.
Most simply put, umami is the flavor of the glutamates, a group of amino acids (though even that definition may be too restrictive). It’s best identified in miso and similar Japanese soups. It’s also supposedly the “meaty” kind of taste in, well, meat, along with seaweed, asparagus, mushrooms, tomatoes, fish sauces, soy sauce and many others.
But umami also involves descriptions of “impact” or “bigness”—descriptors that have more to do with flavor than with biochemical taste. The closer you look at umami, the less clearly it is defined. I found that at least some of its proponents aren’t willing to define it strictly as a “basic taste.”
Back in my childhood, MSG (the most commercially useful form of glutamate) was marketed as a “flavor enhancer,” not a “basic taste.” And those basic tastes were sweet, salty, sour and bitter, as shown on the classic (and rather reductionist) tongue maps in biology textbooks.
So what’s changed? Well, MSG is still marketed as an enhancer with a combinatory effect on other flavors—which makes it all the more bewildering that it’s also being marketed as a “basic taste.” But the big change has been the public fear over health problems—some with validity, many without—related to MSG, which appears to cause allergic reactions in high doses. Around the time that controversy picked up steam (certainly by the 1982 founding of the Society for Research on Umami Taste), MSG manufacturers went into overdrive trying to spread the word “umami” and define it as a “basic taste” as homey as the other familiar four.
At the same time, food scientists have come to realize the four “basic tastes,” codified only relatively recently, are far too restrictive in describing what goes on in our mouths. “Mouthfeel,” for example, is a term that gained momentum.
These two forces met, and by about five years ago produced some fascinating discoveries about glutamate taste, and also a whole lot of muddled marketing.
Before jumping into the fray, it’s imperative to look at the origins of both the “basic tastes” model and umami.
Salty, sweet, sour and bitter are virtually universally recognized, both in time and places. (Note the distinction here between taste, which is something sensed directly by the tongue/mouth, and flavor, which can involve olfaction, vision, expectation, etc.) But until relatively recently, several other essential tastes were recognized, some of which are being resurrected by modern food scientists.
I’ve seen our “four basics” described as Aristotelian, but that’s not accurate. Aristotle viewed sweet and bitter as the “simple flavors,” of which “succulent” and “salt” were elaborations. Between them he also detected “the pungent, the harsh [rough in some translations], the astringent, and the acid.”
Asians and others long recognized hot, as in chemical hotness from peppers, as a basic taste. Others mentioned in Western literature over the centuries include “insipid,” “fatty” and “metallic.” (Metallic, which occurred to me early in my thinking as an obvious basic taste, is indeed undergoing a renaissance, as some metals prove to have a direct taste reaction.)
As explained to me by Dr. Joseph Brand of Philadelphia’s Monell Chemical Senses Center—the guy who did the cat research that dragged me into this whole mess—everything but our four basics was cast off by psychological testing in the 1800s, which showed that those four tastes were the most commonly and consistently experienced and described.
Things like hot, acidic and astringent are now considered “chemical senses”—sheer irritants of the mucous membranes, more akin to pain than taste. But considering they’re all used as elements of food, that’s pretty arbitrary. It’s a bit like saying heat isn’t part of touch.
Psychological test matrices are still part of taste research. But tastes are fundamentally defined—and discovered—biochemically today. Does a molecule trigger an ionic or metabolic reaction within a taste bud pore or not? Sweet, salty, sour and bitter substances do, with unique receptor sets.
We have to be very careful about that definition of taste, however. A molecule triggering a reaction doesn’t result necessarily in a direct taste experience in the brain.
“This doesn’t, however, translate
into a ‘basic taste,’ whatever that is,” I was told by Harry Lawless, a
professor and sensory testing researcher at
Some molecules actually inhibit the nerve from reacting to the substance (or to other substances). Taste receptors typically work in concert with combinatory effect; psychologists tend to talk about “flavor profiles” rather than singular tastes, and even the traditional basics are recognized as bleeding into each other. Some of the reactions biologically don’t result in flavor, but rather in a monitoring effect to see if the liver should take digestive action, etc. Such complexities are part of the umami riddle.
Umami began with an awareness of the shifting definitions of taste, and an assertion that umami is the fifth basic one.
In the early 1900s, Dr. Kikunae Ikeda at the Imperial University of Tokyo, Japan, wondered what exactly tasted so good in broth made from dried seaweed and mushrooms. He was able to isolate the chemical as glutamate, and recognized that MSG was a good, stable form in which to use it as a seasoning.
Ikeda coined the name based on the Japanese adjective umai, roughly meaning “delicious.” (Notably, a term describing flavor, not taste.)
“It is the peculiar taste which we feel as ‘umai,’ arising from fish, meat and so forth….I propose to call this taste ‘umami’ for convenience,” he wrote in his 1909 journal article “New Seasonings.”1
Early in the article, Ikeda noted the many former basic tastes that had been discarded, but said umami should be included on the list. “Umami” was convenient to him in more ways than one; he immediately patented his MSG manufacture process and partnered in the Ajinomoto corporation, which is still probably the biggest MSG maker.2
Since Ikeda’s time, the chemical groups of inosinates and guanylates also have been identified as triggering the umami taste. It has also been found to be enhanced by a group of chemicals known as 5’-ribonucleotides (which includes the previous chemicals).
There’s no doubt umami exists as a flavor. Psychological testing has found a consistent grouping of reactions indicating a unique umami experience.
I’ve tasted it myself by downing a half-spoonful of MSG in the form of the Ac’cent flavor enhancer available at supermarkets, which is just pure MSG.
I tried it after six hours without food, to have a pure experience. I experienced an initial salty taste on the front of my tongue, along with a near-numbness, and accompanied by a slight caustic feeling on the back of my tongue. Then there was a kind of flavor explosion as the MSG dissolved, turning into something close to the familiar flavor of Japanese miso soup, which seemed to move to the back of my tongue. It lingered for several minutes, clinging to my gums and palate.
Eating that heap of Ac’cent, it seemed easy to embrace umami. But umami resists any kind of pinning down, even a loving one. For instance, in most industry literature promoting umami—from the International Glutamate Information Service, for example—you’ll be told that MSG by itself either has no flavor at all or tastes bad. Its magic comes only when it’s used as a seasoning. Apparently, I was completely delusional.
Of course, the industry talks about MSG only as an enhancer because that’s its commercial value to them. No one will buy MSG just to eat clumps of it like breakfast cereal (though am I currently engaged in a protracted willpower struggle to keep from dipping into the can of Ac’cent sitting here on my desk).
But then why does the industry also promote umami as a “basic taste,” apparently oblivious to the paradox of selling a combinatory “enhancer’s” taste as fundamental?
That’s
because of the anti-MSG paranoia that began in 1968 with reports of allergic
reactions caused by Chinese food heavily laced with the seasoning. (It is
widely acknowledged that high doses of MSG indeed cause relatively minor
allergic symptoms; studies have not borne out wilder claims.) The hit the MSG
industry took as a result can’t be overstated. When I went to one of
Umami, a “basic taste,” has become a way to market MSG into something unthreatening and sensuously exotic. It sounds more like feng shui than a laboratory chemical. (Following the stereotype, I find several writers claiming that umami is some kind of ancient Asian wisdom dating back hundreds or thousands of years.)
Brand noted, “The one that needed this [umami] to become a basic taste was Ajinomoto” for both “marketing” and “from a health and safety point of view.”
“They were smart in that they sold it not as a taste stimulus but as a flavor enhancer,” he said. “That moved it away from something that was a possible toxin in people’s minds to something more like table salt.”
“I think to some degree the word ‘umami’ stuck because we didn’t have anything else to call it, and Ajinomoto wanted to keep it exotic,” said Brand, noting that British and Dutch food scientists, who have a concept of “savoury” foods that we don’t, often use that term interchangeably with umami.
It’s interesting to note that Ikeda himself later used and recommended for English-speakers the simple term “glutamate taste.”
With the sexy Asian name in place, Ajinomoto and other corporations began intensive research into proving umami is a basic taste.
Machiavellian or not, the research indicates there are indeed unique taste receptors on the tongue for glutamate. (And even earlier, it was demonstrated that the brain and some nerves react specifically to MSG.)
The receptors are a family of three receptors that work in pairs, responding variously to different molecules. (Or sometimes, not responding at all.)
On one particular pairing, Brand said, “They threw glutamate at it, and it lit up. So everyone on my side of the fence [biochemists/neurologists] said, ‘That’s the fifth basic taste.’ The reason I call it a basic taste is because it has a unique receptor.”3
But whether taste is a spectrum or a singularity is open to much debate. You can quickly fall down a Kantian rabbit hole on this one. While the industry glibly markets umami as a proven fifth basic taste, even believers like Brand see much more complexity.
He notes that in mice, the same set of taste receptors respond to a wide variety of amino acids, and that the same could go for us. In fact, it’s certain ours also respond to the ribonucleotides.
“The whole concept of glutamate being the only umami stimulus is probably wrong,” he said. “This is where the umami thing gets very dirty, because glutamate is not umami.”
The aforementioned complexities of exactly how reception translates—or doesn’t translate—into flavor also apply here. It’s also impossible to find a coherent definition of umami; descriptions range widely and include various lists of foodstuffs.
Brand also noted a couple of key flavor observations. One is that umami has intangibles such as what he calls its “bigness”—that sense of explosion I experienced, also known as “impact” in the MSG industry.
Another is that different glutamate substances taste different. Glutamic acid and glutamic salts taste significantly different, he said. Likewise, potassium glutamate tastes different than sodium glutamate, “which tells me the sodium is doing something different from the glutamate,” he said. “Something ain’t right.”
Of umami, he said, “It’s got to be more than just [the taste receptor pair identified]….I say that’s combinatorial. But the fact there’s a unique receptor [pair] for glutamate makes me want to say there’s a unique glutamate taste.”
It’s a long way from that facile declaration in the popular press to this kind of ultimately philosophical enigma. Science, which is mostly constrained by hard-won facts, is still struggling.
Marketing, which can say virtually anything it wants, is plowing ahead. Umami is already trickling into other food fields, such as the notoriously gullible and faddish world of wine connoisseurship. It appears the term is mainstreaming rapidly and is likely to be accepted well ahead of the evidence.
It must be said that reality may soon match the marketing in one way. If umami is in part an attempt to verbally sanitize MSG, the other tactic would be to find an MSG replacement that has an umami taste. Brand said the industry is researching this constantly, and he’s heard rumors that a couple of molecules have been discovered that indeed cleanly trigger the umami receptor pair. Patents are surely pending.
The concept of umami has done good by expanding the way flavor gets talked about, and in identifying flavors rarely talked about in the West (particularly in food-ignorant America). But it’s also introducing a fad for exotic Asian names for extremely abstract, New Age-y, possibly non-existent flavors.
One such is
kokumi, pitched by Ajinomoto as “the newest Japanese
flavor concept” at a trade expo in
It appears kokumi may just be another MSG sanitization; the ingredients of Ajinomoto’s main kokumi product are just glutamate-laden items.
The vibe I get from the whole umami discussion is that something is deeply wrong, but it’s hard to feel out what it is. Is umami bullcrap? Or is the idea of “basic tastes” bullcrap? Both?
I can’t help but get excited about what looks like a revolution in the study of taste—and start dreading the new wave of mushy-headed food fads.
1 In the “Journal of the Chemical
Society of
2 Dr. Barbara Ruch,
professor emerita of Japanese literature and culture
at
Dr. Ruch also notes that, marketing
fog aside, umami is a “perfectly good, intelligible, uncontroversial” common Japanese
word, the noun form of the adjective umai. She breaks down the definition of umai as “1)
delicious, appetizing; 2) skillful, accomplished; 3) felicitous; 4) splendid,
excellent, fantastic.” As with adjectives in our own tongue, we see the usual
broadening of meaning, which MSG manufacturers have taken to new realms of
elasticity.
3 Cats, incidentally,
rely exclusively on that same receptor pair, though they may experience taste
differently from us. But it could be said they live in a world of umami.
4 More etymology from Dr.
Ruch: In Japanese, kokumi is the noun form of the adjective koi, meaning “1) heavy, dark (as in colors like
dark green, deep blue); 2) thick, as in thickened liquids like soup, pudding,
gravy, or axle grease for that matter; 3) strong, as in espresso coffee.” It
can relate to mouthfeel in terms of a “preferred”
thickness to a substance “as opposed to runny or lumpy.” “Not a flavor, but
definitely a consistency,” Dr. Ruch said. A true mouthfeel
word in Japanese, she added, is hagatai, “the degree of pleasing density felt when
something is chewed with the teeth…often commented on when discussing the
infinite variety of noodles,” among other dishes. I expect a hagatai hagiography
from the MSG industry any minute now.
Significant sources not cited in the text include:
Additional articles falling under “A Paper of Historical Significance,” Barry
Ache, Robyn Hudson, David V. Smith, R.A. Steinbrecht
and Takashi Yamamoto, “Chemical Senses,” 27, 2002; www.ajinomoto-usa.com; Faye Culver,
B&G Foods; “De Anima” by Aristotle, R.D. Hicks, translator; “De Anima” by
Aristotle, J.A. Smith, translator, at http://classics.mit.edu/Artistotle/soul.html;
“Dictionary of Herbs, Spices, Seasonings, and Natural Flavorings” by Carole J. Skelly; “Flavor, Taste and the Psychology of Smell” by
Warren Gorman; “The Forgotten Senses” by Donald E. Carr; “In Bad Taste” by
George R. Schwartz; “Receptor and Transduction Process for Umami
Taste” by Joseph G. Brand, “Journal of Nutrition,” 130:942S-945S, 2000; “Senses
and Sensibilities” by Jillyn Smith; Umami Information Center, London, England; www.wholeflavors.com. Posted