The Science Behind Beer Foam: Why Belgian Beers Have Superior Foam Stability

Craig: today, we're talking about beer, but not just taste. we're talking about the insane physics happening inside your glass. a massive seven year study just revealed the foam on a belgian triple is actually a structural marble that might hold the key to a safer electric vehicles and greener cleaning products. researchers at eth zurich have spent nearly a decade cracking the code on why some beer foam lasts forever while others go flat instantly. they discovered that the belgian beer utilizes a specific physical phenomenon, and let's see if i can get this right, the meringue honey effect to create a self repairing foam shield. this is headline news because this exact same science is now being used to stop dangerous mechanical failures in electrical cars and create eco friendly soap. what's going on here, john?

Jon: yeah. this is cool. so this was seven years in the making. and so they cracked the code on beer foam stability. and so, like you said, they discovered that different types of beer use completely different physical mechanisms to keep their foam from collapsing. and belgian triple beers, they maintain foam what's through surface tension differences, which you talked about the marangoni effect, which, well, they call it the marangoni stresses. so while loggers, they rely on protein rich films that create elastic bubbles. so that's the difference here. right? so the research started this is cool. when a belgian brewer gave a simple answer to how do you control brewing? and he said by watching the phone. and so this breakthrough has applications far beyond beer, like you said. now the key finding here is that there's no one size fits all for stable beer flow. the physics operating in the belgian triple is fundamentally different from what's happening in a lager, and brewers need to understand which mechanism is at work to optimize their product. so when we're talking about this, we're talking lager beers where the foam stability is controlled by surface viscoelasticity. then we've got belgian single beers where the protein rich shells behave like densely arranged small spherical particles on the bubble surface, and that creates a two dimensional suspension. then you have belgian double beers or double beers, where the proteins form a net like membrane structure around bubbles, and that creates an even greater stability stability than the single beers. and what emerged from this is ltp one emerged as a pivotal protein in beer foam stability, and that's because of its role is complex and context dependent. so during the brewing process, it undergoes critical transformations, glycation, denaturation, and lipid binding. so there's a bunch of this is really cool. there's a bunch of chemical reactions at play and a lot of chemistry at play here, far beyond just getting that two or three finger head on your beer. right?

Craig: absolutely. and keeping it there.

Jon: exactly.

Craig: you know, think of, beer foam like a building. loggers build a stiff rigid wall, which eventually cracks, while belgian beers build a liquid skin that constantly moves and repairs itself. and that self repairing motion is the breakthrough. so this creates a blueprint for stable bubbles. in beer, that means aroma and flavor protection. but in the real world, that means we can finally control foam in places where we want it, you know, cappuccinos, and stop it in places, where it destroys, machines, like car engines. so, you know, some impacts we might see on our daily life, and we'll get to some other industries is, you know, expect, richer, longer lasting foam in your lattes, as dairy companies adopt these protein structures. or, you know, we talked about safer cars. lubricants in electric vehicles won't foam up and cause engine failure using, these structures. new cleaning sprays can use these natural beer mechanisms instead of harsh chemicals to create suds. so they say the timeline the science is out now. companies like shell are already testing the e b applications while brewers can, start tweaking recipes immediately. where do you think, we're gonna see it first outside the beer industry?

Jon: so i honestly think because the ev industry is so they're trying to be innovative. i think lubricants in, electric beer i'm sorry. electric beer. electric vehicles. so that that could so lubricants in electric vehicles, they can foam up, which create serious safety risks. so they're now working the team apparently is now working with shell to apply these beer foam insights to selectively break down the harmful foams in evs, which is cool. i think there's a bunch of things. there's the food science applications, to collaborate on, milk foam stability, like you said, for coffee drinks, craig, and, sustainable surfacants. so, relying on, so most industrial surfacants rely on fluorine or silicone, not and they're not environmentally friendly. so this could create an eco friendly alternative. so there's a few applications beyond beer, which there's not that many yet, but i'm sure there's gonna be more that we can talk about in the future.

Craig: absolutely. and, it's not if this is complex physics, it's not a magic pill. just adding more protein doesn't work, you know. they have to master, like, with brewers, fermentation conditions to trigger the specific, marangoni, currents. what do you call them? marangoni?

Jon: marangoni. yeah.

Craig: okay. and there's a risk of the over yeah. there's a risk of over engineering in things like coffee and beer because then everything becomes the same. right? if every beer has the same foam, and it's not unique and whatever. but i love how the technology of the foam and beer is now being used in evs. and if you own a ev, keep an eye on maintenance updates regarding lubricant stability. this is the tech that solves the issue, and we wanna be looking at that. anything else on this, john, before we move on?

Jon: so the cool thing i would just wanna talk about the ltp one just quickly because let's

Craig: go.

Jon: so what's fascinating about ltp one is that it starts in barley with zero foam stabilizing properties, but it's the brewing that transforms it through some chemical modifications. so during molting, sugar molecules attach to it through maillard reactions, which is the same chemistry that makes bread crusts brown. during wort boiling, heat unfolds the protein structure, exposing regions that love to sit at air water surface inter interfaces, and the final protein is chemically and structurally different from where it started. the difference about this too is the altitude connection. so there's a geographic element to this. so brewers at sea level, the boil wort at about a 102 degrees celsius, while brewers at 1,800 meters altitude boil at around 96 degrees because of lower atmospheric pressure. and that six degree difference dramatically affects ltp one. so high altitude brewers can end up with 10 to 15 times more ltp one in their final beer, which might explain why certain brewing regions develop particular beer styles. i thought that was pretty cool.

Craig: oh, it's a great note. like, where did all this come from? right?

Jon: yeah.

Craig: and they had unknowingly perfected this technique, right, that causes the. in fact, they were just trying to get the foam.

Jon: which maybe explains why some beers can't be replicated elsewhere unless they're at the same, environmental, atmosphere as others. right?

Craig: and does that mean at different environmental altitude, it would change over time? we'll have to watch.

Jon: yeah. yeah. absolutely.

Craig: that has to do with gravity and air pressure and all those types of things.

Jon: yeah. how's that gonna affect the research that they're doing now? right? because ltp one is is the main antagonist here protagonist here. right? so

Craig: yeah. i'm sure they're researching it. you know, we have some doubts about this and that, but they have to be, handling it to the people testing this and trying to put it in evs and whatnot. yeah. so this proves that beer foam isn't just an aesthetic. it's a sophisticated material that is literally changing how we engineer cars and chemicals. so the next time you order a pint, ask yourself, are you drinking a beverage, or are you having a physics experiment? let me know which beer you think has the best head in the comments below.