A Study of Cultural Methods for the Quantitative Determination of Bacterial Populations of Distillery Mashes.

Quantitative cultural data on bacterial contamination in a distillery are difficult to obtain because ordinary methods will not distinguish between yeast and bacteria. Direct counts are unreliable because of the large number of grain particles which are difficult to distinguish from bacteria. This investigation was begun, therefore, in order to find a reliable cultural method for counting bacteria in distillery mashes. A procedure which seemed worthy of investigation was the "tube count" method which has been used for many years by the Bureau of Dairy Industry of the United States Department of Agriculture in counting lactate-fermenting bacteria in Swiss cheese. Dr. W. C. Frazier of the University of Wisconsin suggested that the method had possibilities in routine work, and under his direction it was used extensively in research work on brick cheese (Garey et al., 1941).