Does vermouth go bad?

I've had the same bottle of green vermouth in my cupboard for years. I use about a teaspoon at a time. Is it still good? What is "good" for vermouth, anyway?

Try one Martini, turn on a camera/selfie, try a second, by the third, you won't care...

But the rest of us will have the answer. SCIENCE in action! What a remarkable idea!

-Ron Carter

I don't know that it spoils, but the taste changes over time, so I wouldn't add years-old vermouth to a drink.

Yes, it does go bad - it's essentially aromatic-infused wine and should be treated accordingly. If you want to truly enjoy vermouth cocktails, I suggest you go and buy a fresh bottle of good stuff, and keep it in the fridge until it's gone.

If it's green, that's not good! I like Noilly.

Vermouth is a tasty addition when you're making sautéed mushrooms.

Maizy said:

Yes, it does go bad - it's essentially aromatic-infused wine and should be treated accordingly. If you want to truly enjoy vermouth cocktails, I suggest you go and buy a fresh bottle of good stuff, and keep it in the fridge until it's gone.

This ^ Although I totally agree with @rcarter31's take on it!

When our wine starts to "go", I'll use it for cooking.

I always buy the smallest bottle of vermouth possible and keep it in the fridge after opening. Cook with it after a month or two and start again. Martinis are too important to take chances with.