The microbiology of alcoholic beverages

Abstract

The revelation that microorganisms were associated with the fermentation of alcoholic beverages probably began in the mid-1600s with the observations of Antonie van Leeuwenhoek in The Netherlands. Using his newly invented microscope, he described the presence of ‘animalcules’ in samples of fermenting beer and wine. At that time, however, microorganisms were not considered to be living phenomena, and it was not until almost 200 years later (1850s-1860s) that Louis Pasteur, in France, demonstrated unequivocally the transformation of fruit juice into wines and wort into beer by the growth and metabolic activities of yeasts. Since then, scientific understanding of the ecology, biochemistry, technology and genetics of microorganisms associated with the fermentation of alcoholic beverages has steadily progressed. A few years after the work of Pasteur, Hansen, in 1882, in Denmark isolated pure cultures of yeasts responsible for the fermentation of beer and used these to inoculate wort to produce beer. This was the beginning of ‘pure culture’ technology for conducting alcoholic fermentations. Until that time, alcoholic fermentations were natural or ‘spontaneous’ events that originated from the microflora associated with the raw materials. Pure culture fermentations were quickly adopted by the beer brewing industry and slowly but gradually adopted by industries for the production of wine, cider, saké and distilled beverages (Rose, 1977).