What is Foam On Beer? And Why Should You Care?

Today we’re going to say “Cheers” to beer foam! Most widely recognized for creating the perfect first sip, beer foam is actually produced with a very specific purpose.

Though it may seem like a byproduct of the production process, foam on beer is actually much more interesting than that.

So why is there foam on top of a glass of beer? And why does it seem to make your drinking experience even better? Keep reading to find out what’s really behind those bubbles at the top of your beer.

What Is Beer Foam?

While some people like the foam and others loathe it, it’s caused by natural chemical reactions during the brewing process. The foam is caused by the production of CO2 in your beer, which as you may have noticed from all the carbonation, is pretty common.

However, the process that goes into making those bubbles is not so simple. The foam on top of your beer is caused by a combination of factors. The first thing you’ll want to note is that carbonation is produced through nucleation.

Surprisingly, nucleation starts with the glass you’re pouring your beer into. Inside these glasses are tiny imperfections that serve as a starting point for CO2 to form. Many beer glasses are even nucleated, meaning that they have purposely made minute imperfections in the sides of the glass to promote CO2 production.

From there, the bubbles gather together and travel upwards to the top of your glass. On the way to the top, the CO2 bubbles bind to aromatic compounds that get trapped within your beer’s foamy head.

From there, it’s all about the tasting experience!

Foam on Beer Stores the Flavor

As all great foamy beers do, the head at the top of the beer preserves the flavor of the beer underneath. Not only is it full of flavor from its trip through the glass, but the bubbles serve to give you a taste of specific ionized molecules and hydrophobic proteins that create a uniquely bitter taste in the foam itself.

To put it simply, the bubbles that float to the top don’t taste the same as the bottom liquid part of your beer. There are different compounds and molecules at play in the foam, giving it a unique flavor that is lost once you get rid of the foam.

This is why brewers stress the importance of head retention. The foam delivers a flavor that is unique to each beer and pour. The goal is to keep this foamy flavor throughout the entire drinking experience.

Beer Foam Captures the Aroma

Not only is the beer foam essential to storing the flavor of your hops, but it also contributes to capturing the true aroma of the beer. In many cases, taste and smell go hand in hand. If you can smell the notes and the scents infused in the beer, your tasting experience will be enhanced too.

The smell of the beer foam is telling of the quality and type of beer underneath too. Without the foam on top, full of aromatic particles, it would be more difficult to smell the flavors and accents in each brew.

Unnecessary Foam: Kegs and Glassware

Unfortunately, not all foam is good foam. For the most part, you want a light head on the top of your drink, but not so much you’re drinking straight gas bubbles. In cases when your beer comes from a keg, you want to make sure you have a special product to remove that bubbling uncertainty.

If you’re serving with a keg, there are different aspects to the pouring process involved. Not only do you have to worry about a proper pour, but you have to make sure you’re getting the most out of your kegs. This is when the ultimate guide to beer FOB comes in handy.

An essential for any brewers or restaurants serving from a keg, this handy device can help you reduce beer costs by using the “FOB” to float on top of the beer and push the beer through the lines without creating unnecessary foam. The foam in the beer line can cause major product loss, and make the beer less enjoyable for you and your patrons.

Or, if you or your patrons simply don’t like too much foam, or you go a little heavy on the head, you can always employ a beer foam scraper. This levels out the level of foam on your beer to the perfect amount so you’re not spilling, tipping, or wasting any of that precious foam.

Lacing on a Beer Glass

Have you ever wondered what those foam rings on beer glasses are? Like when you’ve been steady sipping on a nice stout and the foam doesn’t seem to leave? This is called beer lacing.

Typically very hoppy beers like stouts, ales, and IPAs have the most lacing, but depending on a couple of factors, you could see it with any beer.

If your beer has a decent head on it, as you sip, the remainder of the foam you don’t drink should last on the sides of your glass. However, other factors like cleanliness can determine if you see lacing as well.

Unfortunately, the less clean your drinkware, the less chance you have of seeing that beautiful lacing. Fats and oils inside the glass can break down the bubbles and causing your lace to fade.

Pour Up

Whether you’re a long time beer taster, or you’re just getting into the world of brewing, the foam on beer is a key part of the drinking process. Don’t skip out on this critical part of the tasting process, enjoy the foam!

Now when you see a lacing beer or a perfectly retained head, you’ll know why! In the meantime, pour up, and browse our online magazine for some more healthy lifestyle tips!