In Asian cuisine, it can be found in soy-based foods such as soy sauce and miso, dried fermented foods, kombu and dashi, and dried fish. In Western cuisine, it is present in aged cheese, salami, wines, tomato products including ketchup, and Worcestershire sauce. Mushrooms, especially shiitakes, are also well known for their umami presence, and they are used in many cuisines to add richness to dishes.

Proteins such as beef, chicken, pork and fatty fish contain glutamic acid and, when blended with umami-rich foods like those listed above, provide an enjoyable and satiating experience that lingers long after the meal is finished. Red wine, broiled steak with mushrooms and bleu cheese, ah, what an umami experience!

So what is the benefit of umami? It is a powerful tool chefs can use to help lower the sodium content of a dish, thus addressing an important health concern. Umami is unique in that it enhances the other four basic tastes so that umami-rich foods require less salt in their preparation, another benefit of seasoning with monosodium glutamate. It also tempers bitterness and sour while pushing sweetness.

Just as umami has been clearly recognized as the fifth of the basic tastes, scientists with the Ajinomoto Group in Japan have discovered yet another: kokumi. They identify it as a nondescript taste that can be translated as “heartiness” or “mouthfulness,” and it is especially evident in umami-rich foods.

Kokumi is believed to be the flavor of calcium, so kokumi compounds can be used to create healthier dishes that are lower in sodium and sugar while still maintaining good taste. A study published in the January 2010 issue of the Journal of Biological Chemistry demonstrated that calcium channels on the tongue are targets for kokumi compounds. Previous studies have shown that there is a strong correlation between those calcium receptors and flavor enhancement—thus, the kokumi experience.

At the same time, researchers from Australia have identified their own sixth flavor—fat—once thought to be flavorless. They say that fatty foods trigger a positive taste-bud response and may explain our intake of high-fat foods and distaste for fat-free alternatives.

Could there be a correlation between the Japanese sixth taste of calcium and the Australian sixth taste of fat? Cheese, milk, butter—all rich in both calcium and fat and all known to create satisfaction and enjoyment. Continued research will tell. The one thing we do know is that discoveries in the area of taste are just beginning, and there is much to be learned.

Renee Zonka, RD, CEC, CHE, MBA, is managing director and associate dean of Kendall College’s School of Culinary Arts, Chicago.

Photo: Blue cheese, rich in calcium, lends both umami and kokumi flavor to dishes such as these sage- and canela-rubbed lamb chops with grilled peaches, Wisconsin buttermilk blue cheese and tempranillo reduction. Courtesy of Wisconsin Milk Marketing Board.