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No More Foamy Beer, Thanks To Magnets 130

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.
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No More Foamy Beer, Thanks To Magnets

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  • by Anonymous Coward on Saturday December 13, 2014 @04:18PM (#48590331)

    Magnets... how do they work?

  • From the abstract of the original article: "When hydrophobins and hop extract together were submitted to magnetic fieldmore gushing was obtained than in the absence of magnet. This is due to the extensive dispersion of the combination by the magnet and can be limited by using less amount of hop extract."

    • by Sneftel ( 15416 ) on Saturday December 13, 2014 @04:49PM (#48590475)

      Exactly. Brewers *already* have anti-foaming measures at their disposal. The most well-known is Fermcap, a silicone-based solution which reduces surface tension. The use of hops -- in extract form or otherwise -- has nothing to do with reducing foaming, and everything to do with flavor, aroma, and preservation.

      • This isn't really a new anti-foaming measure, it's making them more effective. That was the point, the magnetic field made the particles tinier so they could disperse and bond more per unit.

        But you appear to be wrong about hops only to do with flavor, aroma, and preservation as at least one beer maker and several scientists seem to think it has to do with combating too much foam also.

        • Re:Got it backwards? (Score:5, Informative)

          by Sneftel ( 15416 ) on Saturday December 13, 2014 @05:59PM (#48590819)

          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.

  • However I'm not a big fan of Belgian-style beers.

    • My favorite beer was called "Hops Candy" because it had so much hops in it. All I see coming from this is that, in the name of saving money, they found a way to make mass produced beer taste even worse.

      But at least the bar will be dry.

    • Actually, there's a lot of "Belgian style" beers marketed to Americans that consist of lager with clove extract and orange oil thrown in. Uh uh.
      If you want to avoid a trip to Flanders, the best you can do in this country is the Ommegang brewery in Cooperstown, NY.

      Enjoy your Bud Lite.

  • Beer should have a natural head formed by CO2 from fermentation. In the UK live Cask ale is killing off pasteurised keg beer with added gas because it tastes better.

    • Re: (Score:2, Informative)

      by Sneftel ( 15416 )

      The carbon dioxide produced by fermentative carbonation is chemically identical to that involved in forced carbonation. I agree that cask ale tastes better, but that has nothing to do with where the CO2 is from. Purely looking at the gases part of the equation, it has much more to do with the *level* of carbonation, and the oxygenation provided by sparkler nozzles.

      • Re:Head (Score:4, Insightful)

        by WillKemp ( 1338605 ) on Saturday December 13, 2014 @05:25PM (#48590641) Homepage

        It's probably got more to do with the fact that cask ale is brewed, while the other revolting piss is manufactured.

      • Pasteurisation denatures the proteins in the keg Beer which why the head on keg beer don't last and that allows the C02 escape in the glass and that is why Keg beer has the metallic smell. The gas added to keg is also a mix of nitrogen and C02 to try and minimise that metallic smell.

        The naturally produced C02 of cask is retained by the head and also includes aromas from the Beer particularly the hops.

      • Re:Head (Score:5, Funny)

        by MrHanky ( 141717 ) on Saturday December 13, 2014 @06:53PM (#48591051) Homepage Journal

        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.)

    • by Anonymous Coward

      It is so hard to persuade people from outside the UK that the fizzy piss they drink is not the only beer, let alone not the best beer.

      It's very annoying when people call themselves experts in beer, while only discussing the fizzy stuff !

      • by Smauler ( 915644 )

        Nearly all the lager drunk in the UK is foreign - Carling is the only major exception. Some of the foreign beer like Fosters is brewed in the UK under license though. It is originally Australian, though, obviously.

        Nearly all the "real" beer drunk in the UK is English, Guinness being the only major exception, though this is brewed in the UK too (though I assume Guinness drunk in Northern Ireland is brewed in Ireland, but I may be wrong).

        • by Smauler ( 915644 )

          Oops, I'm wrong (about Guinness). All the Guinness consumed in the UK (and the US) is brewed in Dublin, apparently. I wonder where I got the notion it was brewed in England.

          • by Smauler ( 915644 )

            Ok, I'm going to stop replying to myself soon. It used to be brewed in north London between 1936 and the mid 2000's. And I agree with AC above about its "real" beer credentials being a little dubious now.

            • Ok, I'm going to stop replying to myself soon. It used to be brewed in north London between 1936 and the mid 2000's. And I agree with AC above about its "real" beer credentials being a little dubious now.

              Compared to home brew stout, Guinness is like drinking water. A friend and expert home brewer made a batch of stout once. I had a glass at his place, then went to the pub and had a pint of Guinness. I literally could not taste it.

              • I don't mind "fizzy piss", but if I visit any of the newer Pubs that specialise in craft beer then going from a real beer to the fizzy piss makes it undrinkable. Same goes for meat, cheese, or any food in general. The real stuff is worlds better than the manufactured stuff, it's just the real stuff is not easy/affordable to consume on a daily basis.
          • maybe because they had a brewery in nw10 london near the inner ring road. I remember that from around 87-88 when i was working in the area

        • Unfortunately most Guinness is pasteurised, the unpasteurised Guinness is said to not 'travel well' however if you can get it is vastly superior.

          This is a pity because with modern logistics it should be possible to distribute it to most of the UK while it is still fresh.

          • There was a Pub in Boston that I had the pleasure of visiting in 1986 that had their Guinness flown in from Dublin. I was quite fond of Guinness at the time. The combination of it being served at room temp, and being astonishingly fresh had me thinking that I'd been drinking stale beer back home in CA. I didn't get to experience that again until I visited England in 2005 during a layover on my way to Russia. I gave up drinking Guinness after that. Here on the west coast it just doesn't taste right.

    • I visited London over the summer, and went on a tour of Fuller's brewery. It was amazing. I wish that cask ale was more popular here in the States. I'm not aware of a place within 150 miles that I can get it. At least I still have a bottle of Fuller's Vintage Ale [] (bottle conditioned) that I brought home to save for a special occasion.
  • by CaptainLard ( 1902452 ) on Saturday December 13, 2014 @04:47PM (#48590469)

    Beer overflow seems to occur more frequently in the smaller refrigerator I have in the basement. When I open a beer bottle or can (usually a craft beer) it will often overflow, something that almost never happens in the upstairs kitchen. It runs a little cooler than our main refrigerator and the bottles are often horizontal. Are these two factors contributing to the overflow? Is the downstairs beer more excited to get in my belly? Whats the science behind it?

    • by HappyDrgn ( 142428 ) on Saturday December 13, 2014 @04:57PM (#48590513) Homepage

      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.

      • by Kjella ( 173770 )

        Since this is /. and the upstairs kitchen is probably his mom's it's more likely telling him to take a shower because even the beer is trying to flee from his man cave.

    • Re:Home mitigation? (Score:5, Informative)

      by Hussman32 ( 751772 ) on Saturday December 13, 2014 @05:26PM (#48590655)

      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).

      • The beer downstairs is definitely colder, probably a little colder than it should be. I've since increased the thermostat but still have the problem. The overflow is directly out of the bottle a few seconds after I pop it so its not related to the pour. Another post suggested the smaller fridge may vibrate more which may be worth investigating.

        As for home brewing, I tried to get my wife into it (a guy can dream right?) but the starter kit has yet to be opened. Unfortunately I have far to many other hobbies

        • If those are home brews, they may be foamers that are caused by contamination when bottling. The only other thing I can think of is the sediment has more surface area if lying flat, and maybe that has something to do with it. Try looking up

    • The basement fridge probably vibrates more than the kitchen one. And maybe isn't as cold.

      • The basement fridge probably vibrates more than the kitchen one. And maybe isn't as cold.

        The worse a beer is, the colder you should serve it.

        • The worse a beer is, the colder you should serve it.

          Maybe. But if a beer's undrinkable at room temperature (VB's an Australian example of that), you shouldn't drink it at all.

    • Should be the other way round - the atmospheric pressure is higher in the basement...

      • Should be the other way round - the atmospheric pressure is higher in the basement...

        I guess the beer experiences a shock upon the extreme pressure delta of getting upstairs. Where exactly does the OP open the beers?

    • Horizontality is definitely an issue for bottle-fermenting beers. You'll mess up the yeasty sediment when turning it around.

      In my experience, extreme cold is only a problem if you get down to freezing temperatures. I've blown up a few bottles by trying to cool them down faster in a freezer. What happens upon freezing is also great for the nucleation of gas bubbles; hence the cloudy appearance of homemade ice cubes, and the measurements of ancient CO2 levels from the bubbles in antarctic ice.

    • Try storing the bottles/cans upright, if you can. This will reduce agitation since you won't have to flip them upright before serving. Also, if they are bottle-conditioned, you won't stir up the sediment as much.
  • No (Score:2, Informative)

    If you get too much foam, maybe you should clean tour glass and improve your skills in pouring a beer.

    • by Anonymous Coward

      This assumes the keg has been perfectly carbonated. If you've spent any time in a bar, you'll know this is not always the case.

  • Beer is rotten barley water.

    Beer was invented to create a use for grain that had sat too long and gone off.

    It's been a successful marketing ploy for hundreds of years.

    • by Livius ( 318358 )

      So, the invention of marketing pre-dates the 'discovery' of beer?

    • And cheese is rotten milk. It still tastes great though, and perfectly fine to eat. Same with beer (excluding commercial American brands like Schlitz which are universally undrinkable).
      • Or, as Stephen Fry described it, "cheese is the celebration of milk gone off big time stylee"

    • Actually, you have to begin sprouting it in order to make malt, so the grain needs to be relatively fresh.
    • Beer was invented to create a use for grain that had sat too long and gone off.

      Or, it was mostly drunk because beer is safe as the alcohol kills bacteria. Read some history of Europe. People spent most of the time mildly pissed because it was the only not to get something worse.

      Small beer was a breakfast drink.

  • Brewmaster, step away from the tun and put your hands where I can see 'em. You are hereby charged with knowingly violating the Bavarian Purity Act of 1516.

  • Brewers try to tamp down the gushing by adding hops extract, an antifoaming agent that binds to the proteins first.

    Yes, there are hop-based antifoaming agents. However, there are other kinds of hop extract, like the kinds used to add bitterness in lieu of adding hops directly.

    • The ones that give you a nasty hangover, you mean?

      • The ones that give you a nasty hangover, you mean?

        I've never had a hangover from Hop Stoopid. What kind of nasty beer are you drinking?

        • The ones that give you a nasty hangover, you mean?

          I've never had a hangover from Hop Stoopid. What kind of nasty beer are you drinking?

          [_] One that lets him sober up between binges?
          [_] Whatever it is, he's obviously not drinking enough the next morning.
          [_] That's what happens when you mix good whiskey with beer.
          [_] CowboyNeal already drank all the good stuff.

  • I don't drink beer as it doesn't agree with me.....

    But won't this adversely affect the flavour?

  • I seem to recall someone using magnets in the carburetor in some sort of fuel economy scam, is this based on the same thing?

  • I wonder if the hops used as anti-foaming agent has magnetic properties.

  • by Anonymous Coward

    Gushers are typically cause by over-carbonated beer. The hops aren't there to stop foaming, they're there for the dual purpose of being a flavoring agent, and a preservative. I would really not be terribly impressed by a beer with no foam that lacked hops. For one, the hops help to offset the sweetness from the barley malt.

  • How about just preventing the fungal infection in the first place? That's always worked for me, but it's probably too expensive for AB InBev to actually use quality product.
  • I can't see major manufacturers changing their recipes overnight but this is sure to bring an evolution in beercraft. The industry has already been shaken severely through vigorous competition. Major manufacturers will need to put out hundreds of candidate low-hops beers if they don't want to lose ground.
  • Did any one else read this and think they were making stuff up? Using magnets in beer, microorganisms making hydrophobins, antifoaming agent binding to proteins, anti-gushing. Speak English! It's hard enough to compile my object-oriented code using re-entrant methods with my two pass compiler, linking into a MySql relational database without having to wade through a bunch of jargon.
  • by jd2112 ( 1535857 ) on Saturday December 13, 2014 @08:01PM (#48591329)
    Iron Maiden Beer []
    I can hear thier brewmaster now: "Can I Play With Magnets?"
  • I have never seen a bottle of beer overfoam at a bar before unless it was spilled.

    Try not drinking shitty beer.

  • Beer is supposed to have foam! Of course, the donkey pee-pee you guys and the dutch call beer doesn't have any foam, but in Germany a Beer is only well-tapped if it's "Foamcrown" (that's what it's called) can carry a 2-Euro coin.

    Ok, so much for the education. Here comes a beer-joke, somewhat on the subject:
    A guy from Collogne, a guy from Duesseldorf and a guy from Muenster walk into a bar. Mr. Collogne order a "Koelsch", Mr. Duesseldorf an "Alt" and the guy from Muenster a Coke. Both Mr. Collogne and Mr. Du

    • by gatkinso ( 15975 )

      Your beer is a nauseating joke in climates that have more than, oh.... 3 days of sunshine a year.

      In the heat there is only one nation that you can trust with making beer: Mexico.

  • it is perfect already.

  • antifoaming agent is the trick ... and I wouldn't want to have that in my beer. Also nothing worse than getting a flat-looking beer. A good stiff foam crown is very important.

  • We knew they were cool, but we didn't know how cool!

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