Brewing beer: should the airlock top be on during fermentation?!
Brewing beer: should the airlock top be on during fermentation?
The airlock comes with a little lid. Should it be on?
Answers:
Yes that is what it is for the airlock keeps contamination out such as insects, bacteria and dust. The brew mix needs to be kept sterile other than the yeast added for fermentation.
You should fit it to the top and pour a little water with a little food-utensil safe disinfectant into the air lock to prevent water stagnating. As the brew ferments the carbon dioxide given off can escape through the airlock. It will makes bubble sounds as the gas passes through the water inside the airlock. The water in the airlock is a physical barrier from contaminants outside the tub as carbon dioxide is produced it will bubble out of the tub but air can't go into the tub.
Or you can just put a clean cloth over the tub as long as it is completely covering the tub opening then gas can pass through the material.
A recommended disinfectant is baby bottle disinfectant (Milton in the UK) but be careful not to accidently get any in the brew.
Just for info: For every weight of carbon dioxide produce an equal weight of alcohol is produced also. So just think about all that lovely alcohol being made as it bubbles away.
Source(s):
From a family of home brewers
yes
yes - stops them pesky vinegar flies having a bath in the airlock water - which if accidentally splashes back down the pipe will contaminate your beer.
also worth putting half a metabisulphite tablet in the airlock water just to be absolutely safe.
Yes, but don't fret about it. The fermentation will blow it off anyway. Put it back, but the important thing is to make sure the lock doesn't run dry. The water can evaporate depending on how long the process takes.
I didn't used to bother with the lids myself.
absolutely, it has to be or else it will make you sick. it is just like makey liquor out of straight cider. If it isn't completely air tight you will get very sick when you go to drink it because if it isnt it lets air in which creates fungus and other bad stuff
The top of the airlock keeps bugs from flying in...and they will fly in! It also prevents the middle piece (of three-piece airlocks) from popping out.
Philly B has no clue what he's talking about, btw.