Beer foam, whether you’re a fan of it or not, is a staple of many brews. But what exactly is this foam? Many beer drinkers actually don’t know too much about it. As it turns out, there’s quite an interesting science behind the foam on your beer…

Beer Foam: The Science Behind It

How it forms

Beer foam, as you might think, mainly comes from when the beer is brewed. More specifically, it’s due to the creation of bubbles. These bubbles are made through a process known as nucleation. Still, even this process isn’t completely well known.

In general, it mainly comes down to how different proteins react with each other. There is a specific protein in the barley, which has a very high rate of water-resistance. As a result, it tends to cling to the carbon-dioxide bubbles, and rise to the top. Over time, this turns into the foam found on the top of beers.

Foam and flavor

Beer foam can have a pretty notable impact on the beer’s flavor and taste. One the one hand, this is due to the compounds which make it up. However, it is also due to the “effect” it creates when you drink it. It’s this effect which can really make or break a beer’s first impression on you.

Think about when you have something minty and it creates a “cool” sensation. Or, if you have something spicy and it makes a “hot” sensation. The foam can create a similar sensation, depending on the flavors of the beer. It’s more creamy texture can help “soften” your pallet before tasting the beer itself.

Foam variety

Still, not all beer foam is the same. Some beers have a lot of foam, whereas others tend to have little to none. There’s a lot of different factors which can impact the amount of foam that your drink has. For instance, the amount of alcohol in the drink itself can influence the foam it has.

However, there’s some more, even more interesting factors which play a role. Things like glass choices, as well as its temperature, can impact the foam levels. Even things you might not consider, like the food you eat, can influence if the foam on your beer stays or lowers.