Sunday 21 December 2014

Storage of German and English Beer in the 1930’s

Staying with the Wahls, we’re now considering the different storage method employed by British and German brewers.

It stresses the different methods of preserving beer in the two countries. Basically it’s refrigeration versus hopping and alcohol. Sadly, it contains at least one statement which I’m sure is completely wrong.

Preservation during Storage
The high alcoholic content and heavy hopping have a preservative effect so that these beers keep well during the long storage period. For this reason they were made with a high alcoholic content and highly hopped. Substitutes for some of the malt are generally employed in England; these are sugar, rice and corn products. The draft ales and stouts are but lightly bunged by using porous spiles in storage casks and do not foam much when drawn into the glass. Little regard is had for effervescence or foam stability. They should however be as clear as sparkling wines in this respect.

German lager beers are kept in storage at cellar temperatures of 34 to 35 degrees F. which prevents their spoiling. The beer itself when reaching the stock vat or tank has a temperature of about 40 degrees. The vats are exclusively of wood construction. It requires 4 to 6 weeks for the beer to reach within one degree of the temperature of the cellar. During this period the beers are bunged.

The English stock ales and stouts undergo a brisk secondary fermentation induced by a peculiar yeast-like organism saccharomyces Pastorianus. It takes several months before this fermentation is completed. This wild yeast gives to stock ale its peculiar flavor, and it has the peculiarity of fermenting malto-dextrins —a power not possessed by either the bottom or top pure brewers' yeast. The organism Pastorianus develops the fine flavor for which ales and stouts are known and seems to accompany all top yeast in England. Therefore pure culture yeast has found no favor as secondary fermentation could not set in if it were used.
"Beer from the Expert's Viewpoint" by Arnold Spencer Wahl and Robert Wahl, 1937, page 155.

They’re right about adjuncts, but after WW I rice wasn’t normally used. Too expensive, I think.

Cask British beer is more complicated than he describes. A soft, porous spile is only used for part of the process. Non-porous hard spiles are also used to build condition in the cask. Compared to American beer, I suppose it would seem to have little condition.

But the stuff about secondary conditioning yeast is clearly wrong. For a start, they’ve got the capitalisation wrong: it should be Saccharomyces pastorianus, not saccharomyces Pastorianus. It’s not yeast-like, or wild, but a normal brewer’s yeast. Lager yeast is what it’s usually called. That or Saccharomyces carlsbergensis.

But that’s small beer compared to the assertion that it was responsible for the aged flavour of British Stock Beers. And that it can ferment malto-dextrins. I can’t believe that it was really in pitching strains.

What’s really odd is that they then go on to discuss Brettanomyces:

Stock and Bottle English Beers
After secondary fermentation is concluded the stock beers both ale and stout are stored for 4 to 6 months in casks after which they may be bottled. Then in the bottle a third fermentation sets in, which, according to Chapman was thought for a long time to be due to the same wild yeast that carries on secondary fermentation but it has been shown (first by Claussen) that certain organisms belonging to the group of Torula which he named Brettanomyces are in reality the active agents. These are closely allied to the true Saccharomyces in which they differ chiefly in their inability to form ascospores. Chapman says "It is highly probable that the characteristic flavor of certain bottle beers (English unpasteurized ales) is to some extent the result of their activity."
"Beer from the Expert's Viewpoint" by Arnold Spencer Wahl and Robert Wahl, 1937, page 156.

So the Brettanomyces only kicked in after bottling? I’m certain that’s incorrect. Six months in a cask would have been plenty of time for it to become active.

I’m confused and disappointed by this section. It’s so wrong in a period when the mechanisms of ageing were known.

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