What is it?
An airlock has many names, often called a fermentation lock, bubbler, trap or just lock, although the proper name is airlock. It is a device used during fermentation to stop air from entering the fermenter whilst allowing the carbon dioxide gas produced during fermentation to escape.
Why you need it
An airlock is a vital piece of equipment in the brewing process. The airlock will stop any oxygen from getting inside the fermenter, whilst allowing any gas made during fermentation to escape. The air that surrounds us has microscopic bacteria that we are immune to, but the fermenting liquid may not be. The bacteria will then attack the fermenting beer, wine or cider and turn it into vinegar - not very pleasant. The airlock is a barrier between the air and the fermenting liquid. Without an airlock, the risk of bacteria getting into the brew is increased significantly.
How do you use it?
The bubbler airlock is the best airlock and the one we recommend. Simply remove the dust cap and hold the airlock under a running cold water tap for several seconds. Remove the airlock from the water, and any water that is not required will be ejected from the bottom. You can also add water in slowly through the top, stopping when the middle chamber is half full. Replace the cap. The airlock can then be inserted into the grommet on your fermenter lid or pushed in a bung first if the opening is wide.
The bubbler airlock is the airlock we use. It is easy to fill, easy to clean and also has the satisfying plopping sounds as the fermentation is taking place. For those with limited head space, there is a smaller airlock available.
If you lose the dust cap, don't worry, use a small amount of loosely packed cotton wool in the top as this will still allow the gas to escape and stop anything from entering the airlock.