Finding Umami with a Fermented Mushroom Dish

The word umami describes one of the five main tastes, alongside bitter, sweet, salty and sour. Over 100 years ago, Dr. Ikeda in Japan discovered Umami as an addition to the already documented four main tastes. Dr. Ikeda found that foods with high levels of glutamate, inosinate and guanylate (the three components of umami) have a distinct savoriness and depth of flavor.

Glutamic acid or “glutamate” is one of 20 amino acids, the building blocks of protein found in a large variety of meats, fish and vegetables. Inosinate is found in proteins such as meat and fish, and there are high proportions of guanylate in items such as dried mushrooms.

Umami’s impact increases when foods are processed by cooking, dehydration or fermentation. Many of our favorite delicious foods from around the globe are fermented. Now we understand why we enjoy them so much. Soy sauce, fermented soy beans, fish sauces, even Parmesan cheese reach high levels of glutamic acid through a lengthy fermentation process. The high levels of glutamate in these products are what our taste receptors recognize as the delicious umami taste.

Japanese culture uses a mixture of dried kombu (glutamate) with dried bonito (inosinate) to create an umami synergy, which is perceived in much higher levels than simply glutamate-rich products alone. In Western cooking, a mirepoix of carrots, onions and celery, which are glutamate-rich, are mixed with the inosinate-rich beef protein to form a delicious soup, broth or stew with flavor depth. In Chinese cooking, scallions, ginger, onions (glutamate) and chicken (inosinate) are combined for their synergistic effects and boost levels of glutamate perceived on the tongue.

A protein does not carry any taste. We can only perceive any kind of taste in our receptors once the proteins are broken down and the amino acid chain begins to break. Once this process happens, what we consider to be “free amino acids” form, and we are then able to perceive the umami taste. Aging a protein will cause the free glutamate levels to increase significantly. This is the same for cheese and the ripening process. Parmesan cheese, one of the most beloved fermented products, has extraordinary levels of free glutamate due to its lengthy fermentation and aging process.

When proteins are broken down, the taste receptors on our tongues allow us to perceive umami. A signal is sent from our taste receptors and stomachs triggering our brains to initiate the digestion of the protein.

I have been studying umami for some time now, experimenting with koji production and various forms of fermentation and building stocks using fermented products to boost levels of umami in my dishes. I recently began working on a recipe that would have a balance of the five main tastes with a strong baseline that we consider umami, sending messages to the brain to delve in for another spoonful.

I began by fermenting oyster mushrooms, which have a high level of glutamate. I prepared the mushrooms, initially dehydrating them and then rehydrating to remove any dangerous toxins, shredding them finely with a knife and combining them with aromatics of shallot, confit garlic and tarragon. The mixture is seasoned with a 2% kosher salt ratio which will aid in developing flavor while the mushrooms are fermenting. It is left to ferment for 72 hours until pungent. Then I cook the fermented mushrooms in a deep and rich chicken stock.

Meanwhile, I have added a significant ingredient for a rich and unique flavor: toasted barley. This warm, roasted flavor works beautifully with the fermented mushroom and chicken stock. After the barley is toasted it is added to the mushroom stock and left to infuse for several hours. The mixture is then strained and seasoned, balancing the rich flavors with brown rice vinegar for a touch of acidity.

Umami-rich salsify is cooked sous vide with aroma of thyme and olive oil and then charred over binchotan white charcoal. A large king oyster mushroom is brushed with clarified butter and coal-grilled, giving a boost of glutamate as the mushroom chars over high heat. I make a tarragon emulsion, which lends itself well to the flavors of the mushroom and barley, gives a pop of anise flavor, and of course, its beautiful green color contrasts the deep mahogany colors.

The dish is finished with some young tarragon leaves, a perfect combination for the coming months in a warming and comforting bowl, sure to rock your palate.