In 1908, chemist Kikunae Ikeda made a momentous discovery: He extracted glutamic acid crystals from giant sea kelp. Those crystals provided the super savory, mouth-filling taste we know today as umami, the fifth basic taste along with salty, sweet, sour, and bitter.
In this episode of What’s Eating Dan?, my friend J. Kenji Lopez-Alt and I take a deep dive into all things umami, talking MSG and harnessing its umami-boosting powers in the kitchen. For more about the science of savory, read on: then watch the full episode below.
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The Power of Glutamates
Glutamate-rich ingredients—think kombu, katsuobushi or bonito flakes, Marmite, Parmesan cheese, nori, soy sauce, fish sauce, anchovies, oyster sauce, tomato paste, ketchup—show up in cuisines across the globe, and also way back in time.
Some of these foods, like kombu, tomatoes, and mushrooms, naturally contain relatively high levels of glutamate. But most of the big glutamate players have achieved their elite status thanks to fermentation and the breakdown of proteins into their amino acid building blocks. Ingredients like soy sauce, fermented bean pastes, and fish sauce fall into this category: Each starts with a rich protein source, either soybeans or fish, that gets transformed into a sauce or paste that is awash in savory glutamate.
Glutamates and Nucleotides: Better Together
Glutamate is pretty powerful, but it gets much stronger when it has help from a friend or two. In the case of glutamate, those friends are a couple of nucleotides called inosinate and guanylate.
If one of these nucleotides happens to be in your mouth at the same time as glutamate, the nucleotide changes the shape of the glutamate receptor on your tongue, allowing that receptor to send amplified savory signals to the brain (think of it as switching from AM radio to HD audio).
This relationship is nothing short of game-changing from a taste perspective: When glutamate and these nucleotides are present at equal amounts in food, the strength of umami is as much as 20 to 30 times greater than with glutamate alone.
Use Glutamates and Nucleotides to Maximize Umami
To take advantage of the special synergy between glutamates and nucleotides in the kitchen, make sure to combine the two in your cooking. Japanese dashi broth, for example, combines glutamate-rich kombu seaweed with nucleotide rich bonito katsuobushi. Caesar salad features the synergy of anchovies (which contain a big hit of nucleotides) and glutamate-packed Parmigiano-Reggiano. Even the humble cheeseburger (where cheese provides glutamate and beef supplies the nucleotides) puts this science into practice.
To learn more about glutamates and nucleotides (including how they make Doritos so darn irresistible), watch the full episode of What’s Eating Dan?, featuring J. Kenji Lopez-Alt, below.