Analysis of fermentation samples from the Speyside malt whisky distillery by denaturing gradient gel electrophoresis (DGGE) revealed numerous lactic acid bacteria including Lactobacillus fermentum, Weissella confusa, and strains related to Weissella kimchii. Fermentation samples from the Strathclyde grain distillery also contained L. fermentum in addition to a bacterium related to L. sanfrancisco. Comparison of these results with data from a previous study of the Glenkinchie malt whisky distillery confirmed that bacterial growth during the fermentations occurred in three phases. There was an initial phase during the first 50 hr that was characterized by declining diversity as rapid yeast growth ensued. This was followed by heterofermentative bacteria predominating, in particular L. fermentum in all three distilleries and weissellas in the Speyside distillery. Finally, homofermentative bacteria related to L. acidophilus and L. delbrueckii emerged in the malt whisky fermentations that practiced an extended fermentation period. This study extends the diversity of lactic acid bacteria associated with whisky fermentations and indicates new species that have yet to be obtained in laboratory culture.
|Number of pages
|Journal of the American Society of Brewing Chemists
|Published - 15 Mar 2003