Warning signs that your whisky is going bad
Hello to those of you who, like me, have a large collection of whiskies that you actually drink at home: a.k.a. open bottles. We love our dram, to stare at it, to sniff it, to sip it and to savor it. But if you've got many open bottles in your house that you're only slowly working your way through, these are a few tell tale signs that your whisky's gone off.
How long can you keep your whisky once it's opened?
Safe to say, a closed bottle of whisky can be kept pretty much indefinitely but once that cork has been lifted, you need to start moving. Scientists differ in opinion but a nice rule of thumb is that your bottle should be finished within two years after opening to guarantee optimum quality. When you start pouring the whisky from the bottle, the space normally taken up by liquid is now replaced by oxygen and oxidation starts. As you keep pouring, more and more oxygen is let into the bottle and this increases the speed of the oxidation. Meaning - the emptier the bottle, the faster you should finish it.
Does the taste change?
Yes. There's no way around it. When the bottle is opened, first off the alcohol will start to evaporate and over time a strong whisky loses some of that strength and can become a lot smoother to drink. Next to that, some of the flavour compounds will disappear as well, changing the overall flavour of the whisky. How these flavours change depends on the whisky but it's hard to predict.
What affects a whisky flavour?
There are several components that impact the flavour and the shelflife of a whisky. We already discussed oxygen but position, light, temperature and even the type of lid can drastically impact your favorite drink. If the temperature in your house is on the higher side, you might want to consider storing the bottle somewhere cooler. Always store your bottles upright to avoid unnecessary contact with the cork. Keep them out of bright light because it affects the color of the whisky and if you have a bottle with a screw cap, tighten that lid once in a while to avoid oxygen seeping in.
Can I smell if a whisky has gone bad?
It might be hard, near impossible, because it won't be like sniffing sour milk. Whisky that has lost strength and flavour compounds will probably smell different than when you first opened the bottle. However, as they say in cooking, the proof is in the pudding. Using your common sense is important here, if it smells off, if your bottle is damaged, if you see or smell mold on the cork, it's better to be safe than sorry.