Back in college, being handed a foamy beer was cause for exasperated eye-rolling. But glance through any beer review these days, and you'll see effusive odes to creamy heads of foam and the delicate lacing they leave behind. What gives?
The foamy head on a glass of beer offers a few different things for our beer-drinking experience. For starters, each one of those little bubbles is carrying a puff of aroma. Breathe deep as your beer settles and you'll be treated to a sensory pre-show of what you're about to taste.
Aroma also plays a huge role in our perception of flavor, maybe even more than the taste itself (as anyone who has ever had a head-cold can attest). Beer brewers put a great deal of work into the aromatic components of their beer, and giving their beer a nice head of foam ensures that the beer drinker will get to appreciate those aromas.
Foam affects the way the beer feels in our mouths, as well. The density of the head gives the beer a creamy quality and a sense of fullness on the tongue. You'll notice this in particular with hefeweizens, farmhouse ales, and other wheat beers. Beers brewed with oats and rye also tend produce excellent heads of foam.
The quality of the foam in any given glass of beer is the result of many of factors: how the beer was brewed, the ingredients used, the level of carbonation, the serving glass, and even how the beer was poured. Foam dissipates quickly if there are any residual oils in the glass or even on your lips (nix the chapstick!). Pouring the beer down the side of the glass rather than straight down the middle will also result in a less than perfect head.
The amount and quality of foam can also depend on the style of beer. As mentioned, those hefeweizens traditionally sport some of the more impressive heads of foam. On the other hand, high-alcohol beers like barley wines and imperial stouts have much less since alcohol inhibits foam formation. The majority of ales and lagers fall somewhere in the middle of these two extremes.
Bottom line: embrace the beer foam. Its presence is very often a sign of good things to come.
Related: Quick and Dirty Guide to American Beer Styles
(Images: Emma Christensen)
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Comments (11)
For whatever reason, many people seem to believe that absolutely no head is the 'ideal' professional pour. Even my boyfriend used to proudly declare the lack of foam after carefully pouring down the side of the glass. I never understood where this came from. I much prefer a bit of foam, especially with nice dark beers.
I was taught the ideal "head" is between 2-4 cm. I think college kids get the idea that foam is bad because that means the keg is empty or not pumping correctly.
Or, that more foam in the glass (plastic cup) means less beer in the glass. I think it's a holdover from a period in our lives that focuses on quantity over quality.
More foam means more CO2 escaped. Also, it depends if you like foam on your lips (and tip of nose?) while sipping. I rather prefer chilling lager feel than bubbling foam. Sparkling clear top is more aromatic than foam. Now a chance to beat me with counter argument. Who cares.. its all personal choice.
Hmm, I've always been taught (first by my beer-loving father, reinforced by my beer-snob husband and friends) that a well-made and -poured beer SHOULD have a foamy head. To achieve that perfect head I pour down the side first, then gradually tilt the glass straight so the last bit of beer foams. It's a timing thing.
How about a lesson on hour to correctly pour a beer from, say, a keg, a tap and a bottle (ok, a can too) to achieve foamy perfection? I would totally read that. Maybe some info about why a perfect Guiness must be poured over some ridiculously long period of time, or why you cut the head off a Stella?
No such thing as bad head.
Like becster.henrich, I was taught from a young age that a well poured beer has a moderately sized head (same pour technique as well). Whenever I get a beer in a restaurant or pub without a head, I always feel like I've gotten a dud. I had no idea people thought any different.
muddymudskipper- HA, reminds me of my bartending days. People would occasionally scoff at the proper amount of head. I would smile, and tell them "there is no such thing as too much head" and then walk away.
As nnb points out, the more foam the less CO2 in the beer. There is no truly correct answer--it depends very much on personal taste. I don't personally care for the bitter flavor (or aroma) of too much foam, and I do like my beer to retain a good amount of carbonation. I follow the same tilt-and-straighten method mentioned above. 3/4" of foam is perfect to me, but I won't fuss over less.
But there certainly *is* such a thing as "bad head" where beer is concerned. I won't quibble over 1/4" but if you're giving too much foam you're cheating me out of ounce(s) of ale I paid for.
Allison, I believe the slow pouring is meant to ensure a creamy vs. a bubbly texture, and the beheading is meant to help avoid spillage.