At Serious Eats we have a thing for our salt. And rightly so. Salt is pretty awesome stuff, at the very core of what so much of cooking is about. For the next few weeks, we'll be exploring the enormous breadth of culinary salts available to cooks. Along the way we'll take a nod to science, dispel some myths, and consider why salt is one of the most important edible substances on Earth.
What Is salt?
Salt is a crystalline mineral composed of the explosive metal sodium and the toxic gas chlorine. Edible table salts, whether mined underground or harvested from water, share this chemical structure, even if their shapes vary. Different treatments of specialty salts, and the unique impurities found inside them, give salt an incredibly wide range of flavors. In the next few weeks I'll discuss some of these varieties in detail. This week I'll be focusing on how and why salt can do what it does.
How Does Salt Work?
The most frequently asked question about salt is how it works. How does it make a tomato taste more like a tomato and a steak taste more like a steak? Salt is one of the very few ingredients that's a flavorant: something that enhances flavors, not just contributes its own. Sugar and MSG are other examples of flavorants, but salt does it like nothing else. The process is complex, and still a matter of academic debate, but here are three ways salt enhances the taste of food.
"Salt activates a whole category of flavor, and in so doing rounds out the taste of whatever it's added to."
We have taste buds designed for it. We have four types (okay, possibly five) of taste buds that detect sweet, bitter, sour, savory, and salty flavors. Our bodies are hardwired to like salt, so it's no surprise that we enjoy the taste of salty food, and prefer salted food to unsalted versions. But there's something else going on here: Salt activates a whole category of flavor, and in so doing rounds out the taste of whatever it's added to. This is as much a psychological process as a physiological one. Taste is a series of sensory information bits we interpret into an experience. By adding salt to activate our salt receptors, we increase the number of information bits considerably, and in so doing create a fuller tasting experience.
Salt plays to our flavor palate. Besides adding saltiness, salt dials up sweet and sour flavors—which our bodies also naturally crave—while downplaying bitter ones, which we tend to avoid. In other words, salt changes the entire flavor profile of a food and shifts it in the direction of flavors we naturally prefer. Try it on some grapefruit: You'll lose much of the grapefruit bitterness while the sweet and sour citrus flavors become more intense. Salt doesn't just act chemically on food; it makes the experience of that food "better" by activating the flavors we love.
Salt releases volatile aromas. Next time you're softening some onions, take a whiff before adding any salt. Then smell again a few seconds after. The onion aroma will be much more pronounced, so much so that you could almost taste it. Since our tongues can only detect sweet, sour, salty, bitter, and savory flavors, we have to rely on our noses to inform much of what makes a food taste a certain way. Salt releases these aromas, even well after being added to food, which allows us to smell and "taste" them all the more readily.
So yeah, salt's pretty amazing stuff—not too shabby for the child of an explosive and a poison. It doesn't just change the taste of food, it changes our perception of those tastes. By learning about salt we get a glimpse into the mind's relationship with how we eat.
Now we're armed to tackle some of the boutique salts on the market. In the meantime, got any questions about salt? Share 'em in the comments.