A cocktail garnished with lime and mint. Once you've finished a drink, the garnishes might go right in the trash. (Deb Lindsey for The Washington Post)

When people talk about “food waste,” they're usually referring to food that's thrown away by farms, grocery stores, restaurants, even home cooks. But an increasing number of bars are also thinking about sustainability, and the next wave in the movement is actually shaping up in your glass — or right on top of it.

For bartenders, a cocktail's garnish is more than decoration. It's an important element of the drink that adds flavor and fragrance, not to mention visual appeal: the Manhattan's twist of orange peel; the mint julep's tufts of mint sprigs; the Horse's Neck with its trademark long, thin lemon peel spiraling down inside the glass.

But when you're done with the drink, all those pretty garnishes go straight into the trash.

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Food is discarded even before then. At many bars, once a bartender removes a strip of citrus peel, the fruit might get squeezed for juice, but the flesh and rind gets tossed.

For Trevor Frye, owner of U Street's Five to One, getting rid of cocktail garnishes is part of his business model. It cuts waste and is more efficient, he says, but it also improves the drinks. “A lot of times I find [garnishes] very inconsistent for flavor,” he says; it's hard to make two cocktails taste the same “unless you're testing every orange or lemon to see how much oil is coming out of the peel.”

So Frye began making his own aromatized liquid garnishes — essentially concentrated orange, lemon and other citrus peels infused with vodka and diluted with purified water — which are sprayed onto cocktails with an atomizer just before they're served. “You get the aroma, you get the flavor, but we're not throwing everything out at the end of the night.”

After trying "100 different ways” to figure out how to work with mint, Frye came up with a method that includes blanching the leaves, freezing the vodka-mint tincture overnight to preserve the color, and blending with a steeped “mint tea.” The resulting liquid has a bright green color and, spritzed onto a glass of bourbon, the smell of fresh mint. More important, Frye says, the liquid lasts four months —using the amount of mint that the bar would have used and tossed in one night.

The garnish-free manifesto goes beyond sprays: On a recent “Martini Monday,” bartenders at Five to One served the drink with a nori-infused dry vermouth to replicate the salty dirty martini-flavor customers love, without the use of olives.

Bars that embrace garnishes are also looking for ways to be more responsible about their waste. At Hank's Cocktail Bar in Petworth, bartenders collect citrus waste: oranges peeled to garnish an Old Fashioned, stem ends of lemons and limes that were cut off before the fruit was sliced into wheels. These are collected in a large glass jar — “They still have a bunch of essential oils and flavor to impart,” explains bar manager Hunter Douglas — along with leftover juice that doesn't taste as bright as it did a day ago.

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The collected refuse is cooked down with sugar and water to make a citrus cordial. The pH is adjusted so it has the same acid levels as a lemon or lime, and “it tastes like a sour mix,” Douglas says. The result is mixed with gin to create the Trash Gimlet, which the bar serves at happy hour, and the “adjusted OJ” cordial is used in the Bag and Sand, a variation on the classic Blood and Sand, but made with Mellow Corn whiskey instead of Scotch, and served in a clear Capri Sun-style pouch.

Some drinks at Hank's are garnished with slices of strawberry, which requires bartenders to slice off the tops, including the leaves. “Instead of throwing them away, we save them and make a syrup” with blood oranges that are used in other drinks, Douglas says.

Since taking over as bar manager at Hank's in December, Douglas has made it his mission to “find a way to repurpose these things we can't find a use for.” In March, Hank's is launching a menu of drinks made with recycled ingredients, dubbed “Trash Humanz,” and is considering replicating the recycling concept at its sister restaurants, which include Hank's Oyster Bar.

Good for the environment, good for the bar and good flavor? These drinks might just catch on.

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