The accidental science of beer

Beer is alive I tell you! Alive!
Beer is alive I tell you! Alive!

Our post on Friday prompted some needling from Alan at A Good Beer Blog: brewing great beer isn’t hard — it’s a ‘simple, traditional skill’. Then today, as promised, Ed chipped in with a typically sharp post querying how we ended up in what seems a topsy-turvy world where stainless steel automation is ‘craft’ and beer brewed using traditional methods isn’t. (It is to us, but our attempts to reclaim the word to include cask ale seem to have failed.)

With all that in our minds, it was odd that, from beyond the grave, Michael Jackson should chip in from the pages of an issue of The Times from 1980, reminding us that brewing’s status — art, craft, science, or something else? — has been confused for a long time, and is far from settled:

For all the painstaking research that has been done on the subject, brewing remains less of an exact science that it is an art. “Only recently have we begun to understand what a remarkable art it really is”, Professor Anthony Rose, a microbiologist wrote in the Scientific American some years ago. “The brewmaster, by trial and error, has been manipulating some of the subtlest processes of life.”

(Rose’s article, ‘Beer’, appeared in the June 1959 edition of the magazine, and lives behind a paywall here.)

Do brewers with degrees, labs and reference libraries, who understand why they do what they’re doing, make better beer than those who just knew it worked?

Jurassic Park

Raul Cano has successfully cultivated yeast from the contents of the belly of an insect trapped in amber 45 million years ago. That’s mindblowing enough.

When you hear that he’s entered into business with a brewer to produce Fossil Fuel Ale using this ancient, super-sturdy yeast, it just gets cooler.

Apparently, it acts like ale yeast at first, fermenting furiously at the top, before sinking to the bottom to carry on working.

Read the whole story at Wired.

And Alan spotted this last year, of course, well before Wired got onto the story…

Nice branding can make things taste better

Nicely branded Sierra Nevada Anniversary Ale
Nicely branded Sierra Nevada Anniversary Ale

We’ve always felt slightly guilty about how easily we are influenced by the packaging and presentation of our beer. This week, however, a friend tipped us off to a piece of research from 2004 which suggests we’re not being entirely irrational.

The experiment showed that people actually had a stronger pleasurable reaction to a soft drink when they were cued up to expect one brand or another, and presented with packaging.

Test subjects were given Coke and Pepsi without being told which brand was which. These drinks are chemically almost identical, as Samuel McClure points out. With no branding to refer to, the subjects showed about the same degree of “neural response” in the “ventromedial prefrontal cortex” in both cases. Then, when they were told which brand was which (when they were “brand cued”) they not only stated a preference for one over the other, but actually, measurably enjoyed it more.

So, maybe when we get all excited by the nice label on a bottle of beer, and the pretty glass it’s served in, and the quality of the head on the beer — stuff that shouldn’t really matter, but does to us — we have a similar chemical-electrical reaction?

We’re not scientists. If anyone would like to correct or elaborate on our primitive understanding of what this research means, go for it!

Beer science — the answers

bunsenandbeaker.jpgWe asked some of our brainy friends to answer a few questions about the science of beer. Tom was the first to respond. He’s a statistical genius, obsessed with lasers, and has studied science at Cambridge and Imperial College. His answers, with lots of disclaimers about how he’s not a chemist and wouldn’t want any of this to end up on the National Curriculum, are below.

1. Tom isn’t sure what to make of the idea that a huge head on your beer will cause the hop oils to migrate and ruin the flavour. He says:

Hop oils are volatile organic compounds, with the ‘volatile’ indicating that they like to evaporate. The evaporation of hop oils is not, however, necessarily a bad thing. Aroma being a component of flavour, you would be left with little from the hops other than bitterness if they did not do so.

I’m puzzled by the word ‘migrate’. To me this would suggest a slow process (perhaps diffusion of the hop oils along the boundaries of the cellular structure formed by the head) but this would then be impeded by the presence of a larger head. A more logical argument would seem to me to be that the hop oils diffuse into bubbles forming in the body of the beer, and that turbulence caused in careless pouring would lead to a large number of these forming at the beginning. Once these bubbles burst, the beer would have a lower level of hop oils than if the beer had been poured carefully, so affecting the flavour. The problem would then be not so much the presence of a large head than the *loss* of the head that negatively affects the flavour.

More generally, I would expect temperature to have a greater effect on the evaporation of hop oils, which is why it might be a good idea to drink beer a bit warmer, and yet another reason (if one were needed) not to go near Carling Extra Cold.

2. Tom thinks clear bottles are a bad idea.

This one I can believe, since many compounds are photoreactive. The breakdown of organic compounds by exposure to light sounds perfectly reasonable. Think of it as sunburn for beer.

3. Tom thinks beer with artificially added carbon dioxide might well taste different to naturally carbonated beer.

Interesting. Carbon dioxide, when dissolved in water, forms an equilibrium with carbonic acid (H2CO3) formed, if it is not obvious, from water and carbon dioxide. The equilibrium is formed slowly however, so artificially carbonated beer may contain higher levels of dissolved carbon dioxide and lower carbonic acid than the equilibrium, so depending how soon after carbonation the beer was drunk it may have a lower acidity than beer with naturally produced carbon dioxide.