Introduction
We all like to use glass things to store our beer in – they are easy to keep clean and sanitize and you can see what’s going on with the beer within glass vessels at all times. The problem is that if they are clear and light can easily get to the beer inside. Light will tend to make the beer skunky – especially if it’s bright sunlight and there are a lot of hops in the beer. If you don’t believe me, take a look at Equation A.
Light Shining on Beer = Skunkiness in Beer……………………………..………… Equation A
If you still don’t believe me, put a measure of a hoppy beer (an American IPA would be great for this) in a clear glass bottle and let it stand outside in bright sunshine for at least 15 minutes. Taste the beer before and after exposure to sunlight. You’ll be amazed at the difference.
I should perhaps stop here and note that some beer drinkers actually like the skunky taste. Some time ago I was speaking with some professional brewers who shipped their product in green bottles and so it was slightly skunky when it was drunk. They converted the production to brown bottles and got a ton of complaints from customers who didn’t like the now non-skunky beer at all. Go figure!
Anyway, any beer that’s stored in clear, blue or green bottles will be at risk of going skunky – so if you don’t want this happening to your beer keep these in the dark. Better still, use brown bottles.
I understand that some newer hop varieties are being used particularly by the bigger breweries that don’t exhibit this skunky behavior.
Using a Bin Bag to Stop Skunkiness
A carboy is really just a big bottle but usually represents the whole batch of beer. If this goes skunky, you’re going to lose all of it or end up giving it to friends you don’t like. If beer goes skunky in a bottle, then you’ve just lost a small amount which will of course irritate you but not make you suicidal and you get to keep your friends.
So, it’s really important to stop sunlight (or for that matter any other light) from entering your beer in a carboy. One solution would be to use carboys made from brown glass; but when did you last see one of those?
Another solution might be to rub SPF 30 sunscreen over the vessel but this is messy and expensive.
My solution is to use a black garden garbage bag. It’s very cheap and effective – see the nice photo below.
Making and Using a Skunkerator
This exercise isn’t really a serious project although you could make it one if you wanted. Because of this, I haven’t listed it in the Projects section but rather left it here among the other skunky stuff.
One of the other projects I worked on was a photometer to measure beer color (SRM). One of the components I used for this project was a 420nm blue LED. I played safe and bought a 10watt version. This was about 100x more powerful than I needed, so I had to get another smaller one for the photometer. You’ll find details of how to make this SRM meter in the Projects pages on some date in the not-too-distant future.
In the meantime, I had this 10-watt blue LED which gave out light that was very suitable for skunking beer. I used a rubber band to attach the LED to a beer bottle and connected it to a 5V power supply and everything lit up nicely. I presented this invention at the 2018 American Homebrewers Association Conference in Providence, Rhode Island. I proposed it as a technique for ruining the competitors’ beers in competitions. Part of the presentation was the video below – enjoy.
If any of you try this in a competition, let the rest of us know how you got on.