Ah, fellow fungalnauts. We feel you. Sometimes we, too, open our fridge to find it bereft of choice edibles. It’s a sinking feeling… one of shame and remorse. “How could I have forgotten them!” But fear not. We have a cheat for you. An instant-gratification for those lonely mushroomless nights. It’s sinful, really… because it’s as simple as a pot of water and some dehydrated fungi. What’s more, you’ll actually get more umami flavor out of them than if you had used fresh. Yes, you read that right. This is because mushrooms are naturally high in glutamates, the amino acids that are responsible for the savory flavor in foods.

Long known to Japanese mushroom growers and consumers, umami is the “5th taste. For a quick flavor refresh, sweet, salty, sour, and bitter are the other four. Some people call it “savory” – but there’s more to it than that.

Umami is the “savory” taste in food. It comes from three compounds that are naturally found in plants, fungi and meat: glutamate (mainly found in vegetables and meat), inosinate (primarily found in meat and fish), and guanylate (highest in plants and mushrooms).

You can think about this amino acid synergy through the ingredients found in dashi: kombu (contains all 3 amino acids), bonito flakes (high in inosinate), and mushrooms (high in guanylate and glutamate).

Dehydrating mushrooms unchains their umami-ness. The process of naturally dehydrating concentrates the amino acids and frees glutamate by breaking cell walls. Then, through slow, moderate heat, umami flavor deepens via the Maillard reaction (the chemical reaction between amino acids and reducing sugars that causes food to “brown” and produce a very tasty flavor and aroma). 

Umami is a tastant (like the other 4 tastes), a water-soluble chemical that produces a taste sensation by activating taste receptor cells (TRCs). A water soluble extraction, like a stock, is a perfect way to extricate mushroom flavor and umami rich chains of amino acids, making these amino acids more readily absorbed into whatever you’re cooking. And your taste buds.

Going one step further, the particular umami you can get from mushrooms, like shiitakes, is unparalleled because they also have an abundance of guanylate. This amino acid increases the strength and duration of umami flavor on our tongue. The kicker here is that there are literally only a handful of foods that provide both guanylate and glutamate. Here’s a handy umami reference site.