What is an airlock?

An air lock is a piece of wine making equipment that keeps air from entering your fermentation container while letting the carbon dioxide that yeast produces to escape. Some people also refer to this device as a fermentation lock. It will keep any harmful bacteria from infecting your wine and ruining your batch.

You can make your own air lock at home. It is similar to a water bong in nature and is really cheap to make if you have the right materials lying around the house or shop.

I am planning on making a tutorial at winemaking-equipment.com if you are interested

How long can I keep a bottle of wine that has been opened?

Open wine will not last very long. If you are planning on keeping it at room temperature then you are going to have a few days before your bottle of wine goes south. If you keep it refrigerated, then you might have a week before it goes bad.

This is because wine is like fresh fruit. It can get easily contaminated by airborne bacteria and what ever nasties that may be floating around.

The best way to keep your open bottle of wine is to transfer it into a clean, small container that has less air in it and then seal it tightly. You then need to put it in the fridge right away. You might even want to put it in the freezer so the temperature drops quicker. Just make sure that you don't forget your wine in the freezer because a wine Popsicle is probably terrible. Maybe, I think that I am going to try that tomorrow.