Saturday, 16 October 2010

38. PONG

I haven’t always been this paragon of grace and sophistication. In my teens I was a very large, spotty/bruised and uncouth apprentice with a love of rugby, food, beer and death metal. Part of the old Stuart was also a talent for flatulence. I wasn’t as talented as Nimmy Eeams at school who could muster a guff on command but for sheer scale and pungency I had no peers. I remember one afternoon after a rather heavy night, working in an airing cupboard. I was facing the hot water tank, unable to see behind and heard footsteps. I assumed that it was the engineer who I was assisting and let rip with what Ross McPharter would have described as a “show stoppa”. I said “woah! That would be the cheese and coleslaw then” and turned to receive the engineer’s approval for my performance. Instead I was confronted with the customer sporting a tray of tea and biscuits along with the kind of scornful expression which would make the devil himself want to curl up and die. This is kind of expression I want the drinkers of this week’s brew Pong to greet me with.

My least favourite beer flavour compound is H2S. The rest of the beer can be superbly well constructed with everything where it should be but if H2S is there at any level above just perceptible, in my opinion the beer is fit only for the sink. There are some assertive classic pale ales which get away with it (just) but a few breweries make gentle, hoppy beers with high H2S which are an affront to beer. They smell like someone has torn one off and unsuccessfully used a hop flavoured air freshener to disguise the act. How can you enjoy a dink which smells like colonic gas? Sometimes I wish that I wasn’t so sensitive to it although as a commercial brewer, I’m glad I’m not. This week’s beer is designed to have loads of bum fume aroma. The main challenge will be to attain high enough levels to retain some after maturation. H2S is removed over time through the action of yeast metabolism and oxidation.

The yeast which Jean-Marie and I used in our collaboration is a high H2S producer so this is going to be the primary source of the stench. I am using high sulphate levels in the water and low free amino nitrogen in the wort to optimise this yeast’s pumping potential. H2S production is a consequence of amino acid synthesis and metabolism so if I keep these low the H2S should be high. I want to keep the other flavours low to keep the H2S on the pedestal, so I am keeping hops and special malt levels low.

Tech Spec:
OG: 1050

Malt: Pale ale and sucrose

Hops: Fuggles

Yeast: Low temperature lager yeast

4 comments:

Jeff Rosenmeier said...

Being in Henley, one of our selling points is: No ass in our glass. I'm super sensitive to this as well and the other 'local' beer is pongtastic...

Dr Brew said...

I always found this to be common in Burton beers such as Bass, Pedigree and Burton Ale hence your high sulphate levels. I also find it in immature beer, which ties in with yeast metabolism. Did you consider formation of DMS in the boil? Lager malt contains more of the precursor due to lower kilning. DMS is also vapourised during post boil steeping.
Lots more ways to get eggy smells!

the Toss said...

"Part of the old Stuart was also a talent for flatulence." Really. The "new" Stuart's trouser rippers don't count then?

Graeme said...

DMS smells like cabbage though - not eggs (though still a valid one in the flatulance stakes). Jeff you're talking about the "fart-in-a-glass" Brakspear then? ;)

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