You know it when you taste it, but what exactly is that indescribably delicious flavor known as umami?
By Leslie Bilderback 08/01/2014
This might come as a shock, but I am a little annoyed. While dining out recently, I overheard a guy at a nearby table describing his food with a generous pinch of pretension. I won’t call him a foodie, because that term makes me cringe — but that’s clearly what he was. The difference between a foodie and a culinary enthusiast, gastronome or gourmet is that a foodie needs everyone to know he is a foodie. Hence, the loud-enough-for-all-to-hear description of the meal, which included “this sauce has lovely umami.” Really? You couldn’t just say, “It tastes good”?
And this is how I knew that guy didn’t know what umami is. Luckily for you, I do. This incident, the ubiquity of the word umami (thanks in a large part to the popular burger restaurant chain) and my desire to release you from ignorance has prompted the following food history lesson.
In the early 1900s Kikunae Ikeda, a chemistry professor at the Imperial University of Tokyo, was curious about his wife’s dashi. Dashi is a broth used in Japanese cooking the way Western kitchens use chicken stock. It is made by simmering a type of dried kelp, called kombu, in water. Ikeda knew that the dashi made everything taste great. However, it did not fit into any of the recently identified taste areas of the tongue — sweet, salty, sour or bitter.
The taste areas Ikeda referred to were first discovered in 1901 by the German scientist D.P. Hanig. He experimented on volunteers and concluded that taste varied around the tongue. A Harvard historian translated Hanig’s paper, deduced levels of sensitivity and plotted them on a graph. The graph was then transcribed onto a diagram of the tongue. Areas of high sensitivity were identified, while areas of lower sensitivity were just ignored. This became the modern tongue map, an oversimplification describing specific areas of the tongue as receptors for specific tastes. At the turn of the 20th century, it was considered groundbreaking. But if you have ever tried to test the tongue map, you know it's a load of crap. Ikeda, who knew a load of crap when he tasted one, suspected it was incomplete.
Dashi fit none of the prescribed tastes. It was simply delicious. To describe it, Ikeda coined the term umami, from the Japanese umai which means “delicious” and mi which means “taste.” To find it, he distilled seaweed broth in an attempt to isolate its mysteries. He worked with other foods too, noting that in every cuisine there was a delicious component — like cheese or meat — that failed to align with the four known tastes. After years of experiments, Ikeda succeeded in isolating a glutamic acid. This molecule was tasteless. But when ionized by cooking or fermentation, the molecule became an amino acid (the component of protein) that could be detected by the tongue.
Though this amino acid, known as L-glutamate, could be detected, it wasn’t really yummy. Ikeda’s genius was in his search for the stable molecule that would bind with L-glutamate and render it delicious. After many experiments, he discovered that the naturally occurring salt found in seaweed did the trick. In 1908 he successfully combined these elements to form an odorless yet delicious powder called monosodium glutamate (MSG), which he successfully patented.
This explained the deliciousness of dashi, as well as other historically delicious ingredients — including protein-based stocks of French cuisine (used unendingly by Escoffier during this same period) and garum (which is equivalent to modern fish sauce), responsible for flavor and fortunes in the ancient world.
Unfortunately, Western science ignored Ikeda’s findings. MSG was soon widely used in manufactured foods like bouillon cubes, Vegemite (mostly leftover brewers’ yeast extract, which is almost pure L-glutamate) and “seasoning salt.” Short-cut cooks everywhere used it to simulate a long and careful rendering of flavor. Still, the bogus tongue map prevailed, and there was no room on it for umami. In 1974, scientist Virginia Collings showed that all flavors can be detected in numerous spots in the mouth, but by then the tongue map was ingrained in the junior-high science curriculum, which is immutable.
Finally, at the turn of the 21st century, umami receptors on the tongue were isolated. Like those for sweetness, saltiness, sourness and bitterness, the human tongue has receptors that taste only deliciousness. People taste umami through receptors for glutamate, which is why, although it is commonly found in its salt form, it is not detected as salt by the tongue. Today, scientists agree that each taste bud contains 50 to 100 receptors for each taste, but the degree of variation is still unknown. Although the tongue map has finally been refuted, the science of taste is still less understood than those of sight, hearing and touch.
Of course, cooks have long known about L-glutamate, even if they didn’t have a name for it. Seasoning “to taste” is how we bind naturally occurring amino acids to salt and render them palatable. Like the process of procreation, man came about this idea naturally and spontaneously. That’s because the human body is damn smart.
The tongue craves taste in relation to what the body needs. Umami is an amino acid, as is meat. Humans need the protein of meat to replenish the body after a long day of hunting woolly mammoths and building pyramids. (And yes, meatless cultures figured out how to simulate this protein eons ago by combining grains with legumes.) An orange tastes so good after a vigorous workout because fruit is rich in energy-giving carbohydrates. Salt balances our bodily fluids and carries nutrients throughout our system. Bitterness and acidity are a warning against the toxicity of spoiled foods.
No, our cave-dwelling ancestors were not craving Butterfingers like I do today. And they would never have developed my love affair with coffee. Taste evolved like every other aspect of humanity. We taught ourselves to enjoy bitter, acidic, fermented and astringent flavors because we enjoyed their effects. You can see this in action by observing the micro-segment of the human population that was brought up on, and has a high tolerance for, highly spiced foods. Over time we ignore the body’s warnings in the name of flavor.
In this age of globalization we can no longer behave like the tongue-map champions who ignored Ikeda’s cultural differences. Our tongues are the same, but our tastes are classified differently from country to country. In China, hot is considered a taste sensation. India adds spicy and astringent. French researchers are working to isolate the receptor for fat. Some consider metallic a taste, and there are even those working to isolate a neutral flavor, as is found in water.
But really, unless you are a scientist, there is no reason for you to isolate flavors. Sure, by all means, learn about what you eat. Be smart about your food choices, and learn to appreciate the great practitioners of culinary art. But do it for yourself. Don’t do it to impress your friends, or your waiter. Because, guess what? It doesn’t impress either. Kikunae Ikeda didn’t experiment for years so that you could brag about your remarkable palate and post pictures of your meals on Instagram. He knew what I know — no one really cares what you ate last night.
Leslie Bilderback, a certified master baker, chef and author of Mug Cakes: 100 Speedy Microwave Treats to Satisfy your Sweet Tooth (St. Martin’s Press), lives in South Pasadena and teaches her techniques online at culinarymasterclass.com.