Thick Stable Beer Foams

Toast

Here's a story about a new understanding of what makes thick beer foams stable:

Scientists unlock secret to thick, stable beer foams

I wonder if this could be applied to bread-making in some way.  After all, isn't bread a thick foam?

One caveat - the writer writes about single, double, and triple fermented brews as if there were multiple fermentation episodes involved.  In actual brewery lingo, I understand, the terms refer to the strength of the beer, with triple (or "tripel") being the strongest.

From the story:

The researchers also analyzed the protein content of the beers and found that one in particular—lipid transfer protein 1 (LPT1)—was a significant factor in stabilizing beer foams, and their form depended on the degree of fermentation. In single-fermented beers, for example, the proteins are small, round particles on the surface of the bubbles. The more proteins there are, the more the foam will be stable because those proteins form a more viscous film around the bubbles.

Those LPT1  proteins become slightly denatured during a second fermentation, forming more of a net-like structure that improves foam stability. That denaturation continues during a third fermentation, when the proteins break down into fragments with hydrophobic and hydrophilic ends, reducing surface tensions. They essentially become surfactants to make the bubbles in the foam much more stable.

It seems to me that a crumb with large, irregular holes fits the first strength better, while the finer more even hole distribution sounds more like the 2nd or even 3rd stage.

TomP

I'd like to mention that, without knowing the ins and outs of lipid transfer proteins, the bartenders at Bar Léo in São Paulo, Brazil have perfected pulling a chopp -- a glass of draft beer -- that is all head and no liquid. It's is the only place in the world I know where you can order a leitinho -- a full glass of gossamer froth. It is neither bread nor beer, but rather a kind of spiritual thing.

Rob

same price, I think -- but, hey, it takes serious chops to pull a whole glass of fluff.

And anyway, as a waiter in Switzerland once said when everyone else was drinking wine and I ordered a beer: "Ah, beer! Ninety percent water, ten percent profit."

Rob

While I was writing this, I decided to look at the link again and it seems that other beer aficionados may have noticed the incorrect description of fermentation in the article…

I'll admit that I'm not an expert on Belgian beer styles, but I agree that the authors may have misrepresented the Westmalle Tripel, Dubbel, and Extra. Westmalle has a process flow diagram on its website that describes a primary fermentation and a secondary fermentation during bottle-conditioning. The product description for all three beers mentions the yeast addition for bottle-conditioning. 

The most apparent difference in the brewing process for the beers appears to be in the density of the beers: Extra, 12° Plato; Dubbel, 16° Plato; Tripel, 20° Plato. The Dubbel description also says that "double" the ingredients are used to brew the beer. Both the Dubbel and Tripel also use candi sugar in addition to malt. This higher density (and the candi sugar, which has undergone Maillard reaction) may be responsible for the effects.