It’s happened to everyone whether you noticed or not. Unfortunately, dirty glassware at bars is a common occurrence. Dirty glassware can effect the flavors of your beer and often times you can’t even tell a glass is dirty or contaminated just by looking at it. There are a few tell-tale signs of a dirty glass that you should be on the lookout for.
BUBBLES STICKING TO SIDEWALL
There a number of things that can leave behind impurities on glassware. The most common culprits are detergent, food, and grease. These things can all introduce unintended flavors in your beer. The C02 bubbles latch on to these impurities – if you see bubbles like this on the side of your glass don’t be afraid to ask for a new one.
LACING & HEAD RETENTION
Dirty glassware can also contribute to poor lacing (foam left on the side of your glass) and bad head retention. This happens for the same reason rubbing your nose and sticking it in your beer makes the head dissipate. Contaminates in beer effect the surface tension of these C02 bubbles, causing them to burst more easily. This is bad because the head of your beer improves mouthfeel and helps lock in carbonation and aroma.
How to Care for Your Glassware
If you’re unsure if your glasses are clean enough, dip them in a little bit of water. If the water falls off in sheets that’s a good sign. If the water easily beads up into droplets then it’s probably too dirty for a good beer. The best way to keep glassware clean is to only use your beer glasses for drinking beer. When your done, immediately rinse them with hot water and avoid soap and detergent. Paper towels and drying cloths can also leave behind fuzz and contaminates so it’s best to air-dry.