Umami

MANCHESTER-BY-THE-SEA -- To hear Anna and David Kasabian throw the term around, you'd think they had been talking about this thing called umami their entire lives.

David calls the first bite of a vine-ripened tomato an ''umami rush." Anna talks about tasting a corn panna cotta designed by Rialto chef Jody Adams as ''having this very light thing in my mouth, but it's slamming me with umami." And when they describe a salad dressing recipe they concocted in their airy kitchen here, David says it balances ''the sweetness, the sourness, the umami of it, and the saltiness."

For the uninitiated, umami (oo-MAH-mee) is the fifth taste, sometimes described as savory or meaty, and distinct from salty, sour, sweet, and bitter. Think of the uniquely round, satisfying taste found in cured or braised meats, aged cheeses, mushrooms, and mature red wine, and you may start to get the idea.

The Kasabians, after some practice, know it when they taste it, and they're spreading the word. A century after a Japanese doctor applied the name umami to the taste of the food compound glutamate, and several years after US scientists isolated the umami taste bud, the Kasabians have written the first Western cookbook on the subject. ''The Fifth Taste: Cooking With Umami" has just gone into a second printing.

The Kasabians were quick studies, turning a potentially academic topic into a lively treatise and soliciting recipes from 25 chefs -- only a few years after either of them first heard the word.

In 2001, the couple sold their Back Bay condo and moved to New York state so David, a refugee from the world of advertising, could enroll at the Culinary Institute of America for a shot at a second career. In gastronomy class, his professor said, ''You ought to know about this. There's something going around called the fifth taste, called umami, but it's no big deal," says David, 55. ''So I wrote it down and thought, someday I'm going to look into this. How could a fifth taste not be a big deal?"

That day came in 2003, when he and Anna, 56, who has written several books on design and architecture, started tossing around ideas for a cookbook. They wanted something new, so Anna sat at the computer, logged on to Amazon.com, and plugged in topic after topic. ''We could do a book about plums," she says. ''No, turns out we can't do a book about plums. What about squash? No, someone's done squash. So then Dave says, what about umami?"

She pauses in the retelling. ''I said, 'What is umami?' "

Bingo. They had their unique topic. In the spring of 2004, David says, a search for ''umami" pulled up a mere 30,000 hits on Google; now it nets more than 600,000. ''When it hits a million, it's mainstream," he says.

TEST YOUR TASTE BUDS Now that you've learned about it, take an umami quiz at www.boston.com/ae/food

But they had to sell a publisher on the idea first. Anna had written for Rizzoli, and when their proposal made it to editor Chris Steighner, he jumped at it. ''I loved the idea because there's nothing like it out there in the market," he said in a telephone interview from New York. Steighner had heard ''little whispers" about umami here and there in newspaper and magazine articles, ''and my appetite had been whetted." But he was not without skepticism. He had heard of the connections between umami and MSG -- more on that later -- and he worried that the subject might have too much new age theory and too little science behind it. The Kasabians convinced him otherwise. ''They had done so much research," he says. ''They made me realize that this does have a real scientific basis."

David describes diving into the ''wormhole" of information about umami, and the cookbook's bibliography reflects the obsession, listing everything from Brillat-Savarin's 1825 ''The Physiology of Taste" to modern journal papers and symposia presentations with such names as ''Responses to di-sodium guanosine 5'-monophosphate and monosodium L-glutamate in taste receptor cells of rat fungiform papillae."

The Kasabians knew they needed to find a way to bring it all down to earth. They decided to approach chefs around the country and ask them to contribute so potential readers would get the message that umami is more than a theory; it can be a way of cooking. They weren't surprised that Asian chefs such as Ming Tsai and Nobuyuki Matsuhisa had already been working with it and eagerly agreed to be part of the book. But French chef Daniel Boulud and Chicago's Rick Bayless, who specializes in Mexican cooking, were just as up on the idea. Even Jimmy Schmidt of the Rattlesnake Club in Detroit started ''carrying on about umami chemistry" when they called him.

The first chef they met with was Jody Adams of Rialto, who was familiar with it, ''but it wasn't immediate," Anna says.

Sure enough, Adams admits, ''I certainly didn't know as much about it as they did."

''It's a little bit elusive, the whole notion, because it's not as clear as sweet, sour, salty, and bitter," Adams said in a phone interview during a train trip to New York City, although she noted that so many cultures' comfort foods turn out to be umami. ''I think that as we become more familiar with it, people will be able to identify it."

That's certainly what the Kasabians are hoping. When they spoke recently at the Cambridge School of Culinary Arts, in an event sponsored by Slow Food Boston, they began with one experiment designed to teach the audience the difference between taste (the tongue's perception of sour, salty, sweet, bitter, and umami) and flavor (taste combined with aroma). They passed around Jelly Belly candies and told each audience member to pinch his or her nose, choose a candy without looking at it, and chew. With no sense of smell at work, the candy merely tastes sour, perhaps a little sweet. Unplug the nose, and immediately you can sense apricot, blueberry, or whatever the flavor may be.

They also spent a good bit of time talking about MSG, the flavor-enhancing additive invented by Japanese chemistry professor Kikunae Ikeda a century ago. In 1907, Ikeda tried to isolate just what it was that made his traditional broth of kombu sea vegetable and dried bonito tuna so satisfying, and to figure out why that something didn't taste sweet, sour, salty, or bitter. He settled on the amino acid glutamate, and he called it umami, a word that had long been used to describe a perfectly pleasing food.

There's more to umami than glutamate, though, and scientists have identified other substances, including amino acids and nucleotides, believed responsible for umami. Yet acceptance of umami has been tainted by its connection to MSG, especially after articles and studies beginning in the 1960s blamed MSG for ''Chinese Restaurant Syndrome" and other maladies, even though the Kasabians write that a series of properly conducted studies later didn't support those findings. Umami is probably far from the final taste to be discovered; David points to January's discovery by French scientists of a taste bud that responds to fat. ''Well, of course," he says. ''Why didn't I guess that?"

The Kasabians were so peppered with questions at the Cambridge event that organizer Rosemary Melli had to cut things short so that audience members could taste what the couple prepared: a vegetarian take on the usually meat-filled muffuletta, using portobellos, roasted peppers, olives, and goat cheese; truffled mac and cheese; and coq au vin ''nouveau," a shortcut of the classic, made with chicken thighs and white wine. There was no MSG in sight.

When I visited the Kasabians' Manchester-by-the-Sea house for an interview and lunch, they did pull out the MSG, but only to run a demonstration designed to help me isolate the effects of umami on my palate. David poured Campbell's Healthy Choice tomato soup into three ramekins each. We tasted one plain, one with a little MSG added, and one with MSG plus a nucleotide that David says helps ''synergize" umami. The difference was astounding. The first was bland tomato, the second was vibrant tomato, and the third was deep, layered, and even complex. ''This is one-dimensional," he said, following the order of the tasting. ''This is two, and this is three or four or even more dimensions."

So many foods naturally contain the amino acids or other ingredients that we sense as umami without processing that the MSG-safety question may be moot. ''I just want to emphasize," David said after the experiment. ''I never use any of this in food. I don't have to."

Instead, they keep such umami ingredients as Asian fish sauce, Worcestershire, and Parmigiano-Reggiano cheese around and have learned to play with the balance of umami with other tastes. ''I put that fish sauce in everything," he says. ''Everything!"

The more mature something is when they buy it, they say, the more umami it probably starts with, because the proteins have broken down into their amino acid components. Umami, the Kasabians write, ''is the taste of amino acids that are ready for our bodies to use." A red pepper, then, has more umami than a green one, and a winter squash has more umami than a summer squash. Umami can also be brought out by dry-aging, curing, or even braising.

''Yes, you can have a delicious steak at $22 a pound," says Anna, ''but if you put that next to a piece of braised beef that you paid $3 a pound for that you cooked for five hours, slow, with umami vegetables, and you taste that, you're going to get a much richer, longer finish."

They're fully aware of the challenge of describing umami to an audience unfamiliar with it. It doesn't exactly lend itself to sound bites. When asked if he has a short way to characterize it, David responds, ''Savory, brothy, meaty, rich."

''But what does salt taste like?" he asks as we dig in to portobello mushroom lasagna and greens tossed with ginger-anchovy dressing, two umami-packed recipes they designed for the Globe. ''That's not easy, either. So the fact that umami's not easy to describe is not an indictment of the idea that it exists. What does sweet taste like? Well, it's . . . sweet."

They often point to the fact that while the concept of umami might be relatively new, the taste has been around for centuries, and not just in Asia. Mediterraneans began making fermented fish sauce 3,000 years ago; a second-century B.C. cookbook called for it in just about everything.

''I'm Italian, Dave's Armenian, and we grew up with a lot of umami," Anna says. ''A lot of us did. There's a reason my mother made lasagna the way she did. Because it had umami. She never knew that, just like Dave's mother didn't know she was developing umami when she was braising beef."

''Some of the most umami food in the world is Scandinavian," David adds. ''They eat herring like crazy. Fresh herring, salted herring, pickled herring."

However natural the umami impulse may be, the term is another story, and that might be the most formidable marketing obstacle for the Kasabians and anyone else trying to explain it. As a foreign word capping off a list of English ones for the five tastes, umami stands out as mysterious. That may argue for a change in nomenclature, but what would the new term be? Anna is tempted to suggest ''savory," which fits nicely into ''sour, salty, bitter, sweet," but then she has a better idea.

She narrows her eyes, smiles, and whispers, ''Yum."

Joe Yonan can be reached at yonan@globe.com.