Science in the brewery: Pure yeast culture and the transformation of brewing practices in Germany at the end of the 19th century

During the 19th century, the introduction of scientific methods and new technologies into the brewery transformed the practice of making beer. The use of steam engines, refrigeration systems, and standardized measuring devices marked a new era of industrial brewing. These changes also encompassed a new understanding of fermentation as a vital activity of the single-celled organism known as yeast. The biological theory of fermentation had direct implications for how brewers handled yeast and how they solved practical brewing problems such as spoiled beer.; Around 1880, a young brewing scientist named Emil Christian Hansen developed a new technique called ‘pure yeast culture’ as a remedy for spoiled beer. Hansen based his technique on the microbiological theories and laboratory methods of Pasteur, Koch, and other scientists. Yet he was also aware that the ultimate success of pure yeast culture in the brewery depended on its adoption by practicing brewers whose professional identity rested on traditional craft skills and artisanal knowledge.; The initial reactions of brewers to pure yeast culture were mixed. Many brewers recognized its benefits and readily adopted the new technique, but others remained skeptical that laboratory procedures should replace traditional practices. In Germany, this debate fell along regional lines. Bavarian brewers and brewing scientists associated with the Wissenschaftliche Station für Brauerei in Munich readily adopted Hansen's technique and quickly embarked on their own research program to expand its usefulness. In Berlin, however, pure yeast culture came under intense criticism for being too detached from the real needs of the practicing brewer. The leading proponent of this view was Max Delbrück, the director of the Versuchs- und Lehranstalt für Brauerei in Berlin. As an alternative, Delbrück proposed his own ‘natural’ system of yeast culture that drew on traditional brewing practices rather than the ‘artificial’ methods of the laboratory.; The debate over pure yeast culture in Germany at the end of the 19th century highlights the importance of artisanal skills in the production and reception of scientific knowledge of brewing. It also exemplifies the conflicting attitudes of traditional artisans and laboratory scientists towards the process of industrialization and modernization.