Aperitif Wines: Like vermouth, many aperitifs and aromatized wines such as Lillet, Dubonnet and Bonal have a wine base. Because they’re also flavored with flowers, roots and herbs, it’s best to keep them refrigerated to keep those delicate flavors from fading or souring.
Fortified Wines: Though they are fortified to a slightly higher ABV, sherry, port and Madeira are just as delicate as vermouth and other aperitif wines. Unopened, they can be kept at room temperature, but once you crack the seal, they should be kept refrigerated. You’ll have about a month of after-dinner sipping and noon-time Sherry Cobblers before the bottle should be relegating to cooking.
Liquor: Unless you like your booze chilled with no dilution, there’s no reason to keep spirits in the refrigerator or freezer. Because the alcohol content is so high and the sugar content is lower than that of liqueurs and other fortified and aromatized wines, there’s no chance of it souring, becoming discolored or going moldy. Leave these bottles on your bar cart to free up some fridge space next to your leftover Chinese food for that bottle of dry vermouth.
Liqueurs: If you’re afraid that your favorite sugar-infused liqueurs have gone bad from sitting out for a while, don’t fret. Though they are sugary and flavored with roots, herbs and other ingredients, they contain significantly more alcohol than a bottle of vermouth or sherry, which will keep it fresh and tasting proper for the foreseeable future.
Syrups: Whether you’ve made simple syrup, fruit-infused syrup, orgeat or any other cocktail ingredient that includes zero to very little alcohol, there’s no way around it—it must be kept in the fridge. Keeping it on your cabinet at room temperature or warmer is just asking for mold, glorious mold.
Brandied Cherries and Cocktail Fruit: While Luxardo cherries—true brandied, maraschino cherries—are best kept in a cool, dark cupboard (they’ll crystalize if refrigerated), they are the exception to the rule. Most other fruits that wind up in cocktails should be kept refrigerated—cocktail onions, maraschino cherries and olives need to keep their chill to preserve their flavor and avoid mold. If you’re making brandied cherries at home, it’s also a good idea to keep them chilled, unless the recipe states otherwise.