Umami and Beyond

What could compel a former marketing executive to pen an entire book on a sensory phenomenon that, at the time, was little acknowledged by the general public outside Asia? The power of umami, that’s what. Nearing his third decade in the advertising biz, David Kasabian figured it was time to move on. In 2001, he enrolled at the Culinary Institute of America, Hyde Park, NY, and during his second week in a course heard a statement that would forever alter his perspective on taste.

“The professor said,” notes Kasabian, “‘You should know about this fifth taste. It’s called umami, but it’s not a big deal.’ I thought to myself, how could a fifth taste not be a big deal? Because what a good chef does is make certain that the entire eating experience is in balance ... And a large part of that is balancing tastes.”

When Kasabian and his wife, Anna, found themselves casting about for a book project, “I remembered umami, started doing some research on it, and found a tremendous amount of misunderstanding—a tremendous amount of contradictory information—and thought that this could be a very powerful topic for chefs,” he says. The result is “The Fifth Taste: Cooking with Umami.”

With umami now getting wider play, both the general public and manufacturers are recognizing just how valuable a tool it can be.

Who you callin’ umami?

Yet the precise qualities that make umami so appealing are notoriously hard for Westerners to pin down. “Umami is kind of diffi cult to describe, but once you taste it, you know exactly what it is,” says Francesca Elfner, director of sales and marketing, BelGioioso Cheese, Inc., Denmark, WI. To her, that means “earthy, full-flavor—like what you get in a well-bodied wine.”

To Otis Curtis, business development manager, DSM Food Specialties USA, Inc., Eagleville, PA, it’s “chicken or beef broth without the chicken or beef. Imagine everything good we associate with broth, minus the characteristics that make it beef or chicken. This is the closest reference we have in Western culture.”

With the list of descriptors running to "savory," "meaty," "rounded," "sweet-salty," "mouth-watering," and even "metallic," perhaps umami is best defined in terms of what it’s not. "When food doesn’t get your attention," Kasabian says, "when you hit it with a salt shaker, poke it around a little bit, and, when you’re done eating, you don’t really feel you’ve eaten very much, chances are, it’s missing umami."

While acknowledging that umami is a little subtler than the more familiar tastes, Kasabian believes that’s “only because we don’t have as much experience with it.” And yet, he says, “It’s always been there. We’ve always loved it.” Western palates have cultivated a fondness for umami for millennia. Our growing understanding of its chemical and physiological mechanics only casts classic recipes like pasta Bolognese, coquilles St. Jacques, and even pepperoni pizza in a new light because it confirms how canny history’s cooks were: They may not have known why certain ingredients tasted so good, but when they did, they played those combinations to the hilt.

Made in Japan

The word umami is a variation of umai, Japanese for “delicious.” Japanese foods are often textbook examples of umami in action. Take soy sauce, which, “in Japanese food culture, means everything,” says Ken Saito, U.S. president, Kikkoman International, San Francisco. It’s the cuisine’s all-purpose seasoning, because its “complexity contains all the flavors you need,” he says.

Even more representative of its complexity is dashi, a savory broth made by simmering dried kombu seaweed with bonito tuna flakes. In fact, a Japanese scientist—analyzing the kombu used in dashi—first identified the compounds responsible for umami. In 1908, Professor Kikunae Ikeda, at Tokyo Imperial University, extracted pure crystals of the amino-acid glutamate from kombu, which he determined as the source of the seaweed’s “deliciousness.” Ikeda eventually sold his patent to the Ajinomoto Company, and the rest is umami history.

The sum of its parts

Pairing certain ingredients achieves an amplified umami effect—like the kombu and bonito blend in dashi. Basic umami arises from the free glutamic acid in foods like soybeans, Parmesan cheese, potatoes, green tea and kombu.

However, notes Kasabian, synergizing umami comes from nucleotides like inosine monophosphate (IMP) and guanosine monophosphate (GMP) found in meats, seafood, mushrooms and dried bonito flakes—the nucleotides actually amplify the umami effect of the amino acids. “So if you eat a little tomato sauce, it’s already pretty umami because you’ve got lots of glutamate in there,” he says. “But if you make the same tomato sauce with mushrooms, which are high in nucleotides, those mushrooms amplify the umami effect.” A 50-50 blend of monosodium glutamate (MSG) and IMP can generate an eightfold increase in umami impact.

Roasting, grilling, fermenting, drying, curing and even ripening and retorting can increase a food’s umami by liberating amino acids. “Really, anything that you do to food that is going to be abrasive to the proteins in some form is going to create umami,” Kasabian says. “One of the reasons dry-aged beef tastes so wonderful is that the natural enzymes in the meat have been given an opportunity to break down some of the proteins. So the umami is amplified because what used to be complete, tasteless protein is now in the form of the amino acids that we get umami from.”

The same goes for cheese. “That’s what you get with a well-aged Parmesan,” says Elfner, “a greater umami effect.”

The great balancer

Perhaps just as exciting as umami itself is the effect it has on other tastes. “When we speak about umami,” Kasabian says, “we speak in terms of savory, meaty, brothy, mouth-filling—words like that.” However, it is ultimately much more. “Umami will enhance sweetness,” he says. “It’ll change the dimension of the sweetness. It’ll change the complexity of the sweetness.”

Researchers believe the method behind this may be a simple matter of human mechanics. “Both the umami receptor and the sweet receptor actually share some mechanical components,” says Ray Salemme, Ph.D., CEO, Redpoint Bio, Cranbury, NJ. “So you can imagine that there may actually be crossover between some umami ligands and some sweet ligands,” the ions and/or molecules that trigger umami.

Consider the high-intensity sweetener aspartame—an amino acid, like MSG.

“There is certainly evidence that umamicontributing ingredients can alter the way we perceive mouthfeel, creaminess and sweetness profiles, especially when using high-intensity sweeteners,” says Curtis.

Product developers at Kikkoman have put this relationship to work in applications like cookies, cakes, gingerbread and chocolate. The company formulated a chocolate ice-cream syrup using 10% reduced-sodium soy sauce and 6% cocoa powder. The resulting syrup, according to company literature, “depressed the extra sweetness of typical ice-cream syrups and enhanced the richness of the cocoa. The result: a deep, nutty, roasted-chocolate flavor.”

Some tout umami’s ability to tone down bitterness—a feature that could make vegetables more appealing to kids. Kasabian suggests adding a little MSG to black coffee and tasting it head-to-head against an undoctored sample. “You’ll see that it is smoother,” he says. MSG’s sodium, while barely registering as salty, helps balance the bitterness.

This balancing act, as well as umami’s reputed “mouth-filling” attributes, hints at its utility in reduced-fat formulations. “Initial studies have shown that some aspects of mouthfeel and the texture of foods can be modified by increasing umami to compensate for reduced fat,” Curtis says. While umami contributes no physical richness of its own, “Most formulators from the 1980s know the other changes that occur when we reduce fat or try to achieve no fat: All the flavors and basic tastes change, acidity goes through the roof, flavors become out-of-balance, and soon,” he continues. “Umami is a great tool to use to control the acid bite and balance the flavor impact.”

Low-sodium savory

Well-controlled sensory evaluations indicate that strategically deployed umami can allow a 30% to 50% sodium reduction in a food. “Say you’re making pasta, and you’re using meat and cheese in the sauce,” says Elfner. “You can actually use a little bit less salt because there’s so much umami in the cheese and the meat.”

Notes Renee Zonka, R.D., associate dean, Kendall College, Chicago: “I take dried shiitake mushrooms and pulverize them to a fine powder in a coffee grinder. Then I dredge fish in that and sauté it.” Thanks to the mushrooms’ umami, “you need absolutely no salt,” she says. “With the flavor profile that develops, you’d swear that there was already salt on it.”

The relationship between sodium and umami is “a connection that is very actively exploited in quite a few sodium- reduction products in the marketplace,” Salemme adds.

Whereas potassium chloride, the industry-standard sodium substitute, can overwhelm with its bitterness when used alone, “an umami system made of any of the well-known umami ligands—it could be MSG, IMP and GMP, or it could be some amino acids, or some hydrolyzed soy proteins—in the context of that potassium/sodium chloride mixture, will dramatically reduce the bitterness that you taste with the potassium,” Salemme says. “And you’ll also see an enhancement in the net saltiness of the food.”

Industry answers

Flavor houses and ingredient suppliers have long seized on the chemical precursors to umami as sodium-reduction agents and all-around flavor enhancers. These include MSG, nucleotides and hydrolyzed and autolyzed protein preparations, the constituents of which effectively are MSG and nucleotides. Hydrolysis of wheat gluten, corn gluten or defatted soy proteins yields hydrolyzed vegetable proteins (HVP) high in umami-inducing amino-acid salts, with some running as high as 20%.

Autolyzed yeast extracts (AYE), depending on the strain of yeast autolyzed, can have a flavor character ranging from mild to noticeably brothy. “Yeast extracts are good sources of free amino acids and nucleotides,” Curtis says. “They also contribute other components, such as peptides, organic acids and minerals that contribute to the overall flavor impact. Therefore, you will typically get a more-complex flavor impact from yeast extract than MSG or nucleotides alone.” Sometimes a directional flavor note is unwelcome. For that reason, Curtis says, “we have developed high-nucleotide or high-free-amino-acid yeast extracts that have a very clean taste. This allows for experimentation in applications where a brothy or soupy character would not be appropriate, such as dairy-based dressings, vegetable side dishes or even coffee creamers.” He’s even heard of the clean-tasting extracts masking the off flavors of functional ingredients in nutritional beverages—“hardly a savory application, and certainly a novel benefit of the umami taste.”

If HVP uses soy or wheat protein, allergies and gluten sensitivities could be an issue. Also, acid hydrolysis of HVP produces 3-monochloropropanediol, or 3-MCPD, a carcinogen. The irony is that HVP originally emerged as a “natural” alternative to “chemical” MSG. But glutamate is glutamate, regardless of whether it comes from a vial in a lab or a bottle of naturally brewed soy sauce. (For more on 3-MCPD, see the sidebar, “Investigating Unwanted Reactions.”)

“Typically, umami flavor potentiators are used at very low levels, because overuse does not really provide additional benefits,” says William J. Ritter, senior director and chief creative flavorist for food flavor creation, Wild Flavors, Inc., Erlanger, KY. “Monosodium glutamate and ribonucleotides are very cost-effective when used appropriately” and, while they’re packed with umami taste, they carry no identifiable flavor. This makes their umami and other taste contributions much easier to control.

Nevertheless, ingredient suppliers, alert to some consumers’ anxieties about MSG sensitivities, have stepped in with a number of new technologies that enhance umami. Kikkoman offers a high-amino-acid natural flavor enhancer made from the microbial fermentation of wheat protein. It appears on labels as wheat protein, salt and maltodextrin; is mild and bouillon-like in flavor; and has a neutral aroma. “Umami is measured by the total nitrogen in a product,” Saito says. “And this special product has less salt and less flavor, but the total nitrogen is high.” It contains about 16.5% glutamic acid by weight.

Wild Flavors offers a natural flavor that, according to Tim Truby, vice president of the company’s food business unit, “doesn’t contain glutamic acid, which is a huge benefit” when aiming toward an audience wary of MSG. “It doesn’t contain any nucleotides or high yeast extracts either, which is the other benefit, because you do get characterizing flavor when you use some of those yeast extracts.” It’s used like a flavor, generally at 0.05% to 1.50% in the finished product, he says.

The umami pantry

Kasabian has been known to put Parmesan cheese in everything from meatloaf to pastas to soups, where the addition of the cheese’s rind sets off a veritable umami bomb. “It does add character,” he says, “and it adds a tremendous amount of umami.”

Another of Kasabian’s standbys is Asian fish sauce, “which is almost pure amino acids,” he says. And he cites mushrooms as near-ideal umami generators. As a rule of thumb, the darker the ’shroom—think portobellos and shiitakes—the more umami it delivers. But any one will work. “All mushrooms, all the way down to delicate little enokis, certainly have lots of umami,” he says. “But something like a dried shiitake is just through the roof.”

That fact apparently is not lost on those of us in industry. According to a Dec. 8, 2007 article in The Wall Street Journal, Stephen Kalil, CRC, executive research chef, Frito-Lay, Dallas, has been tinkering with umami ingredients from Latin America and Asia—cheese powder, anchovy powder, fermented soybean pastes and mushroom powder, among others—in the company’s Lay’s and Flat Earth vegetable and fruit crisps.

The kitchen-cupboard classics may not replace good-old MSG, but they make for a more interesting, decidedly moreumami profile. And it’s all in very good taste.

Kimberly J. Decker, a California-based technical writer, has a B.S. in Consumer Food Science with a minor in English from the University of California, Davis. She lives in the San Francisco Bay area, where she enjoys eating and writing about food. You can reach her at [email protected].

Kokumi—Umami in 3-D?

The sensation of umami eludes easy description. But compared to kokumi, umami is practically black and white. “Typically, we tell people that the best way to describe it is to experience it,” says Brendan Naulty, president, Ajinomoto Food Ingredients LLC, Chicago. “Umami is now considered the fifth taste. Well, the fact is that there may be a sixth. A number of places are now working on mapping the receptor, or receptors, triggered by the kokumi concept. And probably in 2008 we’ll hear something about what they’ve found.”

“Expansion” and “harmony” are two key descriptors that accompany any discussion of kokumi. Producing a mouth-filling sensation beyond umami, kokumi lends “a richness, or a fullness- in-the-mouth type of perception,” Naulty says.

That richness results not from physical viscosity, notes Shuji Matsui, associate director of marketing and business development, Ajinomoto, but rather, is “solely based on taste.”

The company performed a test with 98% fat-free, low-sodium tomato soup and found that as little as 0.05% of its kokumi enhancer boosts tomato flavor and “gives you a kind of richness or thickness that you would expect in a cream sauce,” Naulty says.

The kokumi enhancer consists of small peptides and oligosaccharides, as well as naturally occurring nucleotides, that put it midway between the two. “So you get kind of a supercharged system,” Naulty says. Made from wheat gluten naturally fermented using a traditional Japanese koji culture, it gets a further savory shot from a yeast extract high in nucleic acids. “So it’s a blend,” he says.

Another kokumi benefit lies in its harmonizing function. “It takes the edge off some other compounds that might be in foods,” says Joe Formanek, business development and application innovations, Ajinomoto. “It smoothes everything out, harmonizes it. Kokumi doesn’t have a characterizing flavor of its own, but it has this effect on everything else.”

It exerts that effect in a time-dependent manner. “We developed a way to evaluate kokumi in our laboratory,” Matsui says. “The important factors are time and taste intensity. We usually do not evaluate the effect of time in taste evaluations. But time is a very important factor in kokumi.”