The air lock is filled half full with water, metabisulphite solution or sanitizer to allow CO2 gas to escape the fermenter while not allowing air, bacteria or wild yeast to get into the wine.
Why are Airlocks so important for Home Brewing?
- Firstly, they keep out all of the undesirable micro-organisms that can ruin your wine. Vinegar bacteria, lactic bacteria, and weak wild yeasts are all kept at bay with a properly maintained airlock.
- Secondly, airlocks prevent oxygen from entering your wine. Not only does this prevent oxidation it makes the production of alcohol possible.
- Yeasts only produce alcohol when it consumes sugar. This is only possible once they’ve run out of oxygen. Thus it is critical that a properly set up airlock is used to starve the yeast of oxygen so they’ll produce alcohol.
- Clean and sanitize every part of the airlock and plug.
- Fill airlocks with only clean water.
- Check on your airlock every day.