It’s a problem no beer drinker ever wants, but one I’m sure everyone has faced at some time or another – a glass of creamy white foam with the smallest bit of beer underneath.
Yes, I know some carbonation in beer is essential with a little bit of a nice head, but why is that head of foam so much larger than it should be?
Is it down to the way the beer has been poured? I’m sure the barman tilted the glass as he should, so why has the beer still come out of the beer faucet or beer bottle so foamy?
Are dirty beer lines causing the beer to come out of the tap so foamy? Has the beer been stored at the wrong temperature? Or maybe it’s just faulty beer equipment, a broken gas regulator adding too much CO2 to the keg, or a beer cooler that just isn’t cool enough.
Let’s take a look at what causes foamy beer issues and how, next time, you can ensure you get that perfect glass of fresh draft beer – no spoon required.
What Is Foamed Beer?
Beer foam is caused by the release of carbon dioxide gas when beer is poured. Carbon dioxide (CO2) is a natural byproduct of the fermentation process that occurs when yeast consumes sugars in the beer, producing alcohol and CO2 with the beer under pressure and condensed into a space.
That means when a beer is opened or poured into a glass, the gas bubbles rise to the top and create a foamy layer full of protein, yeast, and hoppy residue. Scientists call it ‘nucleation.’
Nucleation as a whole can be quite tough to grasp, but here comes the science part. In any beer, there are large protein groups and small protein groups, which both act as foam aggregators (create foam). Lipid Transfer Protein 1 (LTP1) are proteins commonly found in the grains used to brew beer.
These LTP1 proteins hate water – so, to get out of a glass of amber liquid, the only way is up! In order to get up to the surface, they latch onto the carbon dioxide bubbles and travel up to the surface with the bubbles.
They then form a shield around the bubble in order to maintain foaminess. The hops also play a role here to solidify the foam to a light, cloudy coating with the help of iso-alpha acids.
The amount of LTP1 found in a single batch can be influenced by the climate from which the grain was sourced. Both impact taste, foam quality, texture, and retention of the beer foam.
Overall, beer foam is a natural byproduct of the carbonation process that occurs during brewing. While excessive foam can be a problem for some beer drinkers, it can also enhance the flavor and aroma of the beer, as the head helps to release some of the volatile compounds in the liquid.
Therefore, the amount of foam that is desirable or acceptable can vary depending on personal preference and the type of beer being served.
Can I Pour a Beer Without Foam?
Pouring a beer without foam can be a tricky task, especially if you are new to the world of beer. The perfect pour requires a combination of technique and patience, but it is definitely worth the effort to get the most out of your beer.
Here are some tips to help you pour a beer without foam.
- Start with a clean glass. Before you start pouring your beer, make sure your glass is clean and free of any residue. Any dirt or oil on the glass can cause the beer to foam excessively.
- Tilt the glass. When pouring beer, always start by angling the glass at a 45-degree tilt. This will allow the beer to flow down the side of the glass, minimizing the amount of foam created.
- Slowly pour the beer. Once the glass is tilted, pour the beer slowly down the side of the glass, being careful not to pour too quickly. Pouring too quickly can cause the beer to agitate and create foam.
- Straighten the glass. As the glass becomes about halfway full, slowly straighten it so that the beer flows directly into the center of the glass. This will help to create a nice head on the beer while minimizing the amount of foam.
- Stop pouring before the glass is full. When pouring beer, it is important to leave a little bit of space at the top of the glass to allow room for the head. Stop pouring the beer when the glass is about three-quarters full.
- Let the beer settle. After you have poured your beer, let it sit for a few seconds to allow the head to settle. This will help to reduce any excess foam that may have formed during the pouring process.
What Causes Beer Foaming?
Several factors can affect the amount of foam that beer produces, including the type of beer, the temperature, and the pressure.
For example, carbonation levels are generally higher in lagers and light beers, leading to more foam. Additionally, colder beers tend to produce less foam than warmer ones, as the colder temperature helps to keep the CO2 gas in solution.
Another factor that can affect beer foam is the glassware used for serving. Glasses with rough or dirty surfaces, scratches, or residual soap can cause nucleation sites or areas where the CO2 gas can collect and form bubbles, leading to excessive foam.
Similarly, pouring too quickly or with too much force can cause the beer to agitate, releasing more CO2 and creating more foam.
Does the Amount of Foam Make a Difference?
From the way it smells to its taste, the way it looks, its rich, creamy mouthfeel, and the way it sounds, different styles of beer can have very different levels of foam.
Just try to imagine a stein glass of Oktoberfest German beer without that large beautiful head of pillowy foam – it just wouldn’t look or taste the same.
Certain beers like stouts or smooth flow keg bitters will use nitrogen, which has a higher density of smaller bubbles to ensure a creamier foam. Nitrogen is a relatively new concept in the beer industry and has revolutionized the way beers pour from a tin with a more stable thick pillowy layer of foam.
When a beer is topped with a head of foam, the flavors in beer taste better as those compounds that permeate the walls of the bubbles rise up from the bottom of the glass.
A creamy head softens the palate, making it more receptive to the subtle flavors, notes, and hoppy undertones in the beer. Not only that but as more flavor compounds rise to the surface of the beer, the aroma is enhanced, which in turn helps to improve flavor.
Should I Pour Beer Without Foam?
No! Despite what we have been saying about trying to reduce the foam of your beer, you shouldn’t cut it out completely. Foam isn’t the enemy: a light topping of bubbles doesn’t damage the drinking experience – eventually, those bubbles themselves fizzle into beer.
Foamless beer will usually look flat and can also be lacking in flavor. Just as champagne should have bubbles and that bit of fizz, a bubbly beer will normally taste much better.
Pouring your beer bubble-free and foamless stops the beer from releasing those natural CO2 gas bubbles which can then release themselves from the liquid in your stomach causing you to feel bloated and full of air.
A more active pour will allow the bubbles to emerge from the beer and release any excess CO2 before you ingest it.
In conclusion, a little foam is okay, even a big foam head on some beers, just remember though – you are drinking a grown-up beer, not a child’s coke float!