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No More Foamy Beer, Thanks To Magnets
sciencehabit writes Few sights at a bar are more deflating than a bottle of beer overflowing with foam. This overfoaming, called gushing, arises when fungi infect the barley grains in beer's malt base. The microorganisms latch onto barley with surface proteins called hydrophobins. During the brewing process, these hydrophobins can attract carbon dioxide molecules produced by the mashed barley as it ferments, making the beer far too bubbly. Brewers try to tamp down the gushing by adding hops extract, an antifoaming agent that binds to the proteins first. Now, food scientists in Belgium have hit upon a technological solution: magnets. When the team applied a magnetic field to a malt infused with hops extract, the magnets dispersed the antifoaming agent into tinier particles. Those smaller particles were much more effective at binding to more hydrophobins, blocking carbon dioxide and decreasing gushing. During tests in a real brewery, the magnets decreased excess foaming so effectively that brewers needed much lower amounts of hops extract—a potential cost-saving measure. Future studies could explore whether magnetic fields alone could reduce foaming on an industrial scale, the team says.
Magnets... how do they work?
Fact: beer has feelings. Your basement beer sees people less and is lonely. Its overreacting to human interaction.
Solution: spend more time in your basement.
Carbon dioxide solubility decreases with increasing temperature (dissociation constant of water increases, and the extra hydrogen ions push out the carbon dioxide molecules, in addition to gaseous solubilty decreasing with increasing temperature because the energy of the CO2 molecule exceeds the solvation energy), so if your downstairs fridge is warmer, the foam will come out more. Things you can do:
-Chill the beer more.
-Cool the outside of the glass with cold tap water.
-Pour a slow stream of beer down the side of the glass (not directly to the bottom). This chills the path of the beer and you are less likely to foam. If you pour directly to the bottom, it'll just push out.
Good luck. Remember RDWHAHB (Relax, Don't Worry, Have A Home Brew).
"Who are you?" "No one of consequence." "I must know." "Get used to disappointment."
A higher level of hop oil (or pretty much any vegetable oil, really) will indeed reduce foaming. But that is primarily of academic concern, because you simply *can't* play with the hop levels without affecting the flavor. A brewer will perfect the taste, aroma, color, texture, etc. of a beer before they even start thinking about practical concerns such as blow-off. Which is fine, because as I said, there are already solutions (pun intended) for blow-off, which don't involve reformulating your recipe.
A brewer who saw excess foaming in his dubbel, and added hop oil to try to combat it, would find that he was no longer making a dubbel.
The opinions stated herein do not necessarily represent those of anybody at all. Deal with it.
The CO2 from kegged beer will have less C14 as the carbon will be from fossil sources. This makes all the difference in the world.
(Maybe not.)