At the acclaimed Little Red Door in Paris, bartenders start nearly every drink on the menu with a dash or two from an unlabeled bitters bottle. The contents: a low concentration saline solution that’s 10:1 distilled water to kosher salt by weight. “It’s not enough that you would know there’s salt in it,” says bar manager Calvin Politi. “But it’s noticeable in the way that it amplifies everything a little bit more.”
He’s not the only one who’s microdosing drinks with salt. As Peder Schweigert from Minneapolis’s Marvel Bar points out, Dave Arnold’s been tinkering with salt for years. In the same vein, Schweigert’s team adds salt to its simple syrup (30mL of kosher salt per 6-liter batch of rich simple syrup). Likewise, at Dante in New York, Naren Young describes himself as making cocktails like “an Italian grandmother cooks,” adding a little salt in both saline and crystal forms, depending on the drink. (Rather than kosher salt, he swears by flaky Maldon.)
The reasoning for salting drinks is entirely physiological. Our palates can detect five different flavors: salt, sour, sweet, bitter and umami. By playing with the balance of these, you can turn certain flavors up or down—particularly bitterness.
Depending on the drink, Politi alters the number of dashes used, while still keeping additions to a minimum: “Low concentration salt actually helps to control or reduce bitter flavors, but amplifies sweet and sour,” he says. Scientists believe that the sodium ions block the palate’s ability to sense the bitterness, making sweetness or sourness more perceptible.
Ultimately, the effect salt has on a drink really depends on the other ingredients it’s joining: citrus becomes brighter, drinks with egg white become more aromatic and drinks topped with sparkling wine get a bit sharper. Here’s a quick guide to dispatching salt in a variety of drinks.
Politi likens the use of salt in stirred drinks to salting a dish as it’s cooking. “[Say] you’re making some food, and you haven’t added salt yet, but you can smell it a little bit and it smells good,” he says. “When you put some salt on top of it and then mix it in, the salt reacts with food and actually helps molecules get released into the air more easily.” Not only does the salt free up the aromatic molecules when combined with water, stirring a drink releases these unbound molecules up into the air, making both the aroma and flavor of the cocktail more available to the drinker.
There are couple of different roles salt can play in shaken drinks. The first pertains to its interaction with citrus. “Saline in low concentration helps to brighten up sour and sweet flavors, so citrus instantly gets a big lift,” says Politi.
In drinks shaken with egg whites, like sours, the effect is a double whammy. The salt will give structure to the whites themselves by stabilizing the protein chains. As in stirred drinks, the agitation helps the salt to free up the flavor molecules; the extreme shaking required for egg-white drinks elaborates this even further.
In a tall, fizzy drink, carbonation acts as what Politi calls a “flavor center,” controlling how flavors hit your tastebuds. Salt does much of the same thing, which means that the two together double the impact. Salt particles will also help augment the sensation of the bubbles in a drink by causing CO2 gas to be released more rapidly.
The reaction between salt and Champagne or sparkling wine has some textural influence on a cocktail, too, creating what Politi considers a more precise sharpness by playing up the dryness of the wine. Another added effect, he says, has to do with masking unwanted flavors that can come from the CO2 or any other gas that makes bubbles in a drink. “If you have carbonated water, you have that distinct flavor of CO2 and salt can counteract that flavor,” he says. At the same time, you get a more pure, heightened flavor from the cocktail itself.