How Long Vermouth Will Stay Drinkable After Opening

The key to maintaining a great home bar is not just stocking it with a wide range of alcoholic beverages — it is also important to know how to store them properly. If you enjoy mixing drinks at home, chances are you have a bottle of vermouth on hand. This fortified wine is a core ingredient of many classic cocktails, including the martini and the Manhattan. Whether or not it is a frequent favorite of yours, vermouth should not be kept on a bar cart or in a pantry with other alcohol.

Once you have opened your bottle of vermouth and made your cocktail, reseal it with the cork or reusable stopper, then store it upright in your refrigerator. When kept in the cool, dark space of your fridge, an opened bottle of vermouth can last for about one to two months. You could store it in the freezer to extend this period up to six months, but it is not recommended since some of the liquid will freeze and will need to be thawed before use.

Why and how vermouth expires

To understand why vermouth expires, it is helpful to know how it is made. Vermouth is defined as a "fortified wine." It starts with wine as a base, which is then "fortified" through the addition of a strong fruit-based alcohol, like brandy, and mixed with botanicals, including herbs and spices such as juniper and cloves. As with any other bottle of wine, it contains fruit and other fresh ingredients that degrade over time. The process of degradation will speed up based on environmental factors, including exposure to light, air, moisture, and heat. Your fridge acts as an easy, useful tool to slow down (but not completely stop) this process.

Vermouth left out at room temperature will not spoil immediately, but it will begin to oxidize. The volatile aromatics that give this liquor its deliciously complex aroma will grow less intense, and its flavor will change to become more astringent and vinegary.

Drinks to make use of your open bottle of vermouth

Knowing that a bottle of vermouth won't last forever, you may want to be somewhat strategic about when you open a new one. You might take the occasion to master the art of making one or two classic cocktails that call for vermouth or host some friends for an at-home happy hour. If you opt for the latter, you may want to consider batched cocktails that you can prepare beforehand so that you don't spend your social time mixing individual drinks.

With just three ingredients each, martinis and Manhattans are perfect for batching. If you're not sure if your guests prefer gin or whiskey, you may want to make a half batch of each. Negronis are another simple solution for making good use of a bottle of vermouth (tequila can be swapped in as the base alcohol in any of these cocktails for those who prefer it). In any event, mix your cocktails the day before your gathering and store the batched bottle in the fridge until you are ready to drink.