New science! No more foaming!!

[Nerdie]

http://news.sciencemag.org/chemistry/2014/12/no-more-foamy-beer-thanks-magnets

"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, the team will report next month in the Journal of Food Engineering. 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."

 

[Fedora]

Wow

 

[schokie]

That's amazing! I've subscribed to that magazine so I can learn more about brewing science. Apparently I've been wasting my time here.

 

[k1ngl1ves]

Wat?

 

[The_Bishop]

Here I was stupidly thinking we were using the hops for flavor!

 

[Talgrath]

So wait, they've been using hop extract to prevent foam? That seems...weird. Is this mainly concerned with light lagers or something?

 

[GilaMinumBeer]

I went one better. I put a ring magnet over my beer line so that the magnet would polarize the CO2 for clarity.

 

[PlinyTheMiddleAged]

I went one better. I put a ring magnet over my beer line so that the magnet would polarize the CO2 for clarity.

I did that once but I found that polarized CO2 made me burp.

 

[GilaMinumBeer]

I did that once but I found that polarized CO2 made me burp.

To counter that, you gotta wire a AA battery to the end of the line. It makes the CO2 cleaner.

 

[stpug]

Less Hops?!?

BLASPHEMY!

 

[Arrheinous]

So reading the paper...

Hydrophobin appears to be a protein in fungus that grows on grain and one of the proteins you extract into solution when making wort. Hydrophobin lets the fungus stick across surfaces better.

The problem they address is that hydrophobin interacts with CO2 and nucleates bubbles while also forming a very stable foam.

Hop extract can block CO2 from interacting with the hydrophobin. The magnet apparently causes the hop extract to disperse into smaller particles. The smaller particles of hop extract are better able to block the parts of hydrophobin that allow it to interact with CO2.

The big idea is that you could use less hop extract to achieve more antifoaming by using a magnetic field to break down the hop extract particles even finer. Because people use hops or hop extract for anti-foaming?

They use a magnet with a force of 0.31 Tesla. MRI can range from 0.5 - 3 Tesla. That's quite a bit. The hop extract can be ripped apart into small forces by being cycled through the magnetic field - the extract has charges like a surfactant (+/-) that the magnet acts on as they pass by a some speed.

They also imply that gushers can arise from 'tainted' grain and a component of it which survives the brewing process. Or this protein may be something that occurs in infected bottles and amplifies the gusher effect when combined with over attenuation/carbonation.



Some of this sounds off though:

"Some hop extracts are used frequently in brewing to control the foam in boiling kettles and fermenters and to increase their capacity for the process. Such extract is a suitable alternative in order to decrease gushing and the result showed that it decreases gushing of beer when it is added before carbonation (Shokribousjein et al., 2014)."

It wouldn't be the first time academia has a limited understanding of the industries they are trying to court. But hey, these researchers are working out of Belgium.

One more bit: "This study was supported by the KUL-University Foundation Hydrophobin Grant by the Duvel-Moortgat, Orval, and Chimay breweries and Cargill Malting." I could see how Orval might want to improve the reliability of bottle conditioned beers with Brett but is that really a problem?

 

[Talgrath]

Interesting breakdown Arrheinous, I'm still confused as to what they are trying to do here though; maybe it's something very specific to the beers of the companies that funded the research?

 

[helibrewer]

Just don't buy Fusarium infected barley.....

 

[Arrheinous]

Interesting breakdown Arrheinous, I'm still confused as to what they are trying to do here though; maybe it's something very specific to the beers of the companies that funded the research?

The big problem I see is that hops / hop extract (which you're going to get from boiling hops for 60+ minutes or longer, especially in some of the Belgian traditions, right?) are for bittering, balancing malt/sweetness, and flavor. Not defoaming which might have the opposite effect of the nice head you see on a tripel or even look at a DIPA.

Unless this is something Chimay or Orval know about. But they've had ages to perfect their process to account for carbonation and conditioning. Maybe the few variables they can't control come down to something as trivial as how much fungus is growing on the raw grain?

What really separates this hydrophobin protein from any of the other (and likely more common though maybe not effective) proteins you get?

Anyone could just straight up ask the researchers. There is a corresponding author who's supposed to handle questions. Email address is Zahra DOT shokribousjein AT biw DOT kuleuven DOT be.

 

[GilaMinumBeer]

The big problem I see is that hops / hop extract (which you're going to get from boiling hops for 60+ minutes or longer, especially in some of the Belgian traditions, right?) are for bittering, balancing malt/sweetness, and flavor. Not defoaming which might have the opposite effect of the nice head you see on a tripel or even look at a DIPA.

This is the part that doesn't jive for me. They are talking about kettle items at serving time. I wonder if perhaps the article was not properly proofread.

I know that FWH is known, albeit limited, in reducing foam in the boil. Much like most other antifoaming agents. It's almost like they have twisted a kettle issue into a serving issue.

 

[Arrheinous]

"In order to study the influence of a magnetic field on the dispersion of hop extract at brewery scale, experiments were carried out in a brewery in Belgium. In this brewery, hop extract is added to the wort after cooling and before transferring to the fermenter.

"Intention is to decrease the foam in fermenters and to maximise the vessel capacity. For the experiment, 800 g hop extract was mixed with 1 L of cooled wort in a small vessel. The mixture was passed through the magnet (0.31 T) by means of a pump to be distributed in 27,000 L of wort."

I'm not sure what kind of foam they are addressing here. Is this foam from agitation of the the wort during transfer or krausen during fermentation?

But then they go on about how hop extract is a 'gushing inducer':

"The major components of the hop extract are waxes (C29 and C31) which are strong gushing inducers (Shokribousjein et al. 2014) while some unsaturated fatty acids were gushing inhibitors.
Based on the total amount of individual molecules in the hop extract, it is found that the majority of the molecules are gushing inducers."

And in terms of how much the magnet is ripping up the hop extract particles? It's going from 2.3 um to 1.94 and 1.94 to 1.35.

Reading into how they test the amount of gushing it looks like this is meant to make bottles less sensitive to being shaken up.

The gushing test was performed according to the Doubly Modified Carlsberg Test (M2CT) for the samples in wort (Garbe et al.,2009). Twenty millilitres of samples, prepared as explained above,
were added to 1 L sparkling waters which were stored at 2 C for at least 24 h. In order to have the same amount of liquid in all bottles,
prior to the experiments, 20 mL of sparkling water was removed and then the sample was added. The samples were shaken on a
horizontal rotating shaker at 150 rpm (Bühler shaker SM30, Germany) for 3 days at 25 C (Bühler TH30 incubator hoods,
Germany). After 3 days, the samples were allowed to stand for 10 min and then turned upside down three times (180) by 10 s
intervals. After the last turning, the bottles were stand for 30 s and then opened. The amount of overfoaming was calculated from
the difference of weight after opening. All gushing experiments were carried out with at least five repeats.