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. This small airlock (handy airlock) is a 2 piece design, the main chamber and a top part.
Why do 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 small airlock is simple to fill with water. Just remove the top part and pour water into the outer chamber, to about halfway, then replace the top. The airlock can then be inserted into the grommet on your fermenter lid or pushed in a bung first if the opening is wide. This type of airlock is almost silent in operation and is smaller than other types - ideal for those with limited headspace.
The more common airlock is the bubbler type. This is larger than the small airlock and is in 1 piece rather than 2. The bubbler airlock is the airlock we use as we can see the fermentation as the water is pushed around the airlock and we also like the satisfying plopping sounds as the fermentation is taking place.
Sometimes it is more difficult with these type of airlocks to see if there is any fermentation gasses given off. Also, as they are a lot quieter, you may think nothing is happening inside the fermenter.