I am not a martini drinker but had a summer visitor who is, so I bought a $15 bottle of dry vermouth to maintain my hostess with the mostest status. She stayed three days, had three martinis, and I was left with 90 percent of a 750-milliliter bottle of dry vermouth.

I was researching how to best store it for her next annual visit when I learned that vermouth doesn’t hold its flavor well over time. It’s not one of those bottles of liquor you can keep in the cabinet in the dark, depleting it by just three tablespoons annually when it’s time to make that duck dish on Christmas.

At its core, vermouth is wine. The wine is fortified with high-proof alcohol (unaged brandy, typically) and flavored with botanicals like chamomile, coriander, juniper, saffron and wormwood. Generally, sweet vermouth is made from red wine and used in Manhattans, and dry vermouth is made from white wine and used in martinis. An unopened bottle of vermouth will keep for a year. Once it’s open, the added alcohol improves its shelf life over straight-up wine somewhat, allowing it to sit a bit longer on the counter, but eventually the taste deteriorates. So it’s best to store all vermouth in the refrigerator, where the cooler temperatures slow oxidation. Even there, you get only a couple of months before the flavor degrades in the direction of vinegar.

In a study conducted by Cook’s Illustrated magazine, test kitchen staff stored open bottles of dry vermouth at room temperature and in the fridge, tasting them every other week. After a month, most tasters found that the vermouth stored in the pantry had lost its citrusy aroma and tasted flat. The vermouths stored in the refrigerator were good for sipping for twice as long, two months total, but after that point they developed bitter flavors.

While I could simply sip my leftover dry vermouth to avoid wasting it, I’ve already got a bottle of Lillet Blanc I prefer as a summer aperitif. Fortunately, in cooking, dry vermouth can be used anywhere white wine is called for in a recipe. It can be used in equal measure to add an acidic element to the rice when making summer risottos. Its herbal tones add great flavor to pan sauces once you’ve seared a piece of chicken, fish or vegetables in said pan. Any shellfish stew – like bouillabaisse or lobster stew – that calls for a tip of a bottle will benefit from a bit of dry vermouth. While sweet vermouth is well suited for chocolate desserts in place of red wine, dry vermouth works well when poaching the stone fruits available this time of year.

Admittedly, the fact I’m looking for ways to spend the leftover vermouth in my kitchen does demonstrate the amount of privilege I enjoy in my life. But wasting it, regardless of my circumstance, is still an unsustainable act.

CHRISTINE BURNS RUDALEVIGE is a food writer, recipe developer and tester and cooking teacher in Brunswick, and the author of “Green Plate Special,” a cookbook from Islandport based on these columns. She can be contacted at cburns1227@gmail.com.

Even in the fridge, vermouth lasts just a few months. Here’s a delicious way to use it up. Gregory Rec/Staff Photographer

Vermouth-Poached Stone Fruit Crumble

This recipe is designed to allow you to use whatever leftover wine, vermouth or cocktail additives you have on hand. You’ll get 3 cups of poaching liquid in whatever combination pleases your palate. I like a little bitterness, so I include 1/2 cup of Campari. If you like your stone fruit straight up sweet, use all vermouth or white wine.

Serves 4

FOR THE CRUMBLE:

1 cup all-purpose flour

¾ cup rolled oats

½ cup brown sugar

½ teaspoon baking powder

½ teaspoon cinnamon

¼ teaspoon kosher salt

1/2 cup (4 ounces) cold butter, cut into small cubes

FOR THE POACHED FRUIT

2 almost ripe nectarines or peaches

2 almost ripe plums

2 almost ripe apricots

1 1/2 cups dry vermouth

1/2 cup Campari

1/2 cup honey

1 vanilla bean, split

2 wide strips lemon peel

To make the crumble, preheat the oven to 350 degrees. Combine the ingredients in a food processor. Pulse until the mixture begins to clump together, about 1 minute, remove it from the food processor and spread it onto a Silpat-lined baking sheet. Bake for 10 minutes, stir, then return it to the oven and bake until it’s golden brown, 5-8 minutes more. Remove the crumble from the oven and set it aside to cool. Once it’s cooled, you can store it in an air-tight container at room temperature.

To poach the stone fruit, cut each fruit in half and remove the pits. Combine the vermouth, Campari, honey, vanilla bean, lemon peel and 1 cup water in a medium saucepan over low heat, stirring until the honey dissolves. As the poaching liquid simmers gently, place the fruit in the saucepan and cover the top with a piece of parchment paper cut to the size of the pan.

Let the fruit simmer in the liquid for five minutes, then flip the halves to ensure they’re evenly cooked. After another five minutes, test the fruit using a paring knife or cake tester — the knife should slide through easily, but the fruit should not feel mushy. Depending on the ripeness of your fruit, the halves will poach at different rates. Use a slotted spoon to remove them from the poaching liquid and set them aside to cool. Reduce the poaching liquid by half by turning up the heat, cool to room temperature and strain the solids. Return the poached fruit to the cooled liquid and store in the refrigerator until ready to serve.

To serve, sprinkle some of the crumble into the bottom of four bowls. Divide the fruit among the bowls. Top with a scoop of ice cream, a 1/4 cup of reduced poaching liquid and more crumble, as desired.