Tuesday, 4 August 2020

Pasteurisation

We're back with Lloyd Hind trying to predict the future of UK.

He seems to have been fascinated by pasteurisation especially its use in stabilising bottled beers. In the 1920s, even for non-bottle-conditioned beers, pasteurising wasn't common in the UK Chilled and filtered bottled beers were filtered, cooled down to precipitate out sediment and then artificially carbonated, though, obviously, such beers would have a limited shelf-life as they weren't biologically sterile, as pasteurised beer would be.

There were still problems with pasteurised beers:

"Given satisfactory pasteurisation any turbidity that arises is due to gradual precipitation of protein matter; fermentation in bottle would point to the use of dirty bottles or failure to secure proper sterilisation. Modern pasteurising apparatus has got over to very great extent the other two difficulties that used to be so apparent, namely, the production of rather objectionable flavour and high percentage of breakage, with loss of bottles and beer. Prevention of steamed flavour does not, however, depend only on the process of pasteurisation; brewing methods and materials have lot to do with it, and in general lager beers stand the heating better than top-fermentation beers."
Journal of the Institute of Brewing, Volume 30, 1924, page 323.

That's the problem I always has with pasteurisation: the funny boiled flavour. For some reason it's particularly prominent with British-style beers. A point which Lloyd Hind makes:

"There are differences, too, in the way in which lager beers will stand up after pasteurisation. The German brewers suffer more in this direction than the American; turbidity came on much more quickly in German export beer, and with turbidity deterioration in flavour takes place but greyness without any change in flavour is enough to make high-class beer unsaleable, or, in any case, let in the opponent's beer in the export market. The advantage gained by the American brewers was due to their unrestricted choice in the matter of materials. The Germans were confined to the use of malt only in the mash tun."
Journal of the Institute of Brewing, Volume 30, 1924, page 323 - 324.

Basically, through the use of unmalted grains, American pasteurised beers were more stable than German ones. That pesky Reinheitsgebot made life difficult for the German brewer.

2 comments:

Barm said...

I am just speculating here but perhaps it is the heavy use of crystal malt in the type of British beers that tend to get exported that leads to the boiled-sweet flavour once they are pasteurised.

Ron Pattinson said...

Barm,

yes, I think the large amounts of crystal didn't help.