If You Spot This Bar Glass Red Flag At A Brewery, Get Out Fast

There are over 9,000 breweries in the United States today. So, how do you know which ones you should frequent? The beer obviously has to be good, and you want a nice atmosphere plus any number of extras like events or food trucks. But there are also things you don't want to find that could help narrow down your choices. Certain red flags at breweries should send you running — away from dirty taprooms or breweries with offensive beer names and toward the breweries doing everything right. One of the biggest, most important warning signs is dirty glassware.

The fact that there are different types of beer glassware signals what a crucial part of the beer-drinking experience it is. Sizes correlate to the alcohol levels of different beers, and shapes evolve out of beer styles' cultural histories and help support aroma-packed foam. But just as easily as glassware can enhance beer, it can ruin it. Most simply and perhaps most disgustingly, dirty glassware harbors bacteria — likely not dangerous enough to pose serious health risks, but that could cause stomach aches and definitely not taste good.

Residue in general could create off-flavors, and grease or oils left on glassware cause the beer's carbonation to dissipate. That means flat beer, with no lovely foam full of aromas. So, not only is dirty glassware a sign you're about to get a bad beer, but it also poses a concerning question: If a brewery isn't even cleaning its glassware, what else are they neglecting?

Sometimes it couldn't be easier to spot dirty glassware. You might see actual smudges, grease, or lipstick stains. But what about when the glass looks relatively clean — is there a way to make sure? Actually, there are a few.

While foam and the bubbles of carbonation are, of course, things you want to see in your beer, if you see uneven clusters of bubbles, especially clinging to one spot, you've got dirty glassware. These pockets of carbon dioxide cling to any spots of dirt or oil inside the glass to form and then release their gas out of the beer. That's why a completely flat beer is also a telltale sign of dirty glassware. As you drink the beer, a clean glass provides an even surface for the residual foam that should be in your beer to cling to, which creates what's called "lacing." If your glass is clean, you'll see these neat rings of foam going down the glass. But they will be unevenly clinging or not form at all because there's no foam to begin with if the glass is dirty. If a glass is really, really unclean, you may even pick up on unpleasant odors.

For the most part, dirty glassware is a surefire signifier that you are not in one of the country's best breweries. But mistakes do happen, and one glass could have somehow gotten overlooked. Politely ask the bartender for a fresh pour — if that glass is dirty, too, get out of there.