Brewing
Modern brewing methods use a low proportion of wheat, generally ranging from 25% to 50%, and deliberately create a sourness either by a secondary fermentation in the bottle (Jackson suggests that traditionally bottles were buried in warm earth for several months), or by adding Lactobacillus. Records from the early 19th century indicate that the beer was brewed from five parts wheat to one part barley, and drunk young, with little indication of creating sourness with either a secondary fermentation or by adding Lactobacillus.
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