Marketing and the brewing process

[Conrad]

I was at a complete loss for a good title, so hopefully I wasn't too misleading

I am trying to keep a better eye on the blogs we follow and quite enjoyed Pete Brown's today. It mentions his bemusement with a Foster's marketing message whilst giving a lesson in brewing (one that I sadly needed).

Anyway the original can be found here.

[Brewguru]

I am trying to keep a better eye on the blogs we follow and quite enjoyed Pete Brown's today. It mentions his bemusement with a Foster's marketing message whilst giving a lesson in brewing (one that I sadly needed).

Yet another piece of mis-information on the part of a multinational brewer. Pete Brown is normally a spot on blogger who is fairly clued up.

He does however make a couple of errors, probably because he is trying to over simplify things or he is implying something that doesn't read right. Alpha acids do not contribute to aroma, they are present in all hops to greater or lesser extent and by a process of isomerisation in the boil cause bitterness (and taste - you can get differing grades of bitterness believe it or not). Hence hops added at the start of a boil cause bitterness. Other organic oils and aroma compounds are vaporised or broken down by prolonged boiling and as a consquence these can only contribute at late hop additions for taste and aroma.

I would wager that they add hop extract at some stage to chemically enhance their amber P*ss. I never touch the stuff so i can't speak from experience, but lager is the German word to store and lagered beer is stored for up to 90 days if done authentically. Bet Fosters don't do that.

Also reminds of of the Stella Black promotion - "matured for longer". No mention of how long "longer" is.

[Conrad]

.... and by a process of isomerisation in the boil cause bitterness .....

Sorry I have to ask this, but do you have any references online that explain this bit, because I am struggling to understand how isomerisation comes into this.

[trainman]

He does however make a couple of errors...
Alpha acids do not contribute to aroma, they are present in all hops to greater or lesser extent and by a process of isomerisation in the boil cause bitterness

I think that's what PB says - the mention of the disappearance of pungent aromas is that of the hops, not the acids (which he then states create the bitterness).

[Brewguru]

Sorry I have to ask this, but do you have any references online that explain this bit, because I am struggling to understand how isomerisation comes into this.

Strictly speaking I am (in a previous life) a physical chemist so not my forte but from what I know it is a structural rearrangement of Alpha Acid's 6 carbon ring to a 5 carbon ring with Hydroxyls becoming Ketones and vice vera. What is formed is an iso-alpha acid which is the bitterness in beer. The molecules are identical in chemical formulae but differ structurally, hence they are isomers? It's a bit like monosaccharides which can do the same ?

more detail here

I have more detailed stuff at home which I can look up and PM if you like

[Conrad]

Thanks for that, a very interesting link!

I did my chemistry degree 15 years back, so my knowledge is rusty and anything more would leave me dead in the water. Still surprised to see that isomerism is relevant (as in they are targeting a percentage for taste), I suppose I shouldn't be as if I remember rightly all natural sugars are an isomer.

Fascinating stuff, I wish I was better at it, also can I say my lecturers clearly missed out on an excellent example to use here .