(TABLE 4) Stillage analysis from another distillery showing poor ethanol recovery from a pot distillation system. SAMPLE ID
well affects turnover time. This should be considered early in the planning process when sizing fermenters and pumps. Also, how quickly can the beer be pumped from the beer well into the column? This will determine how quickly you will empty the beer well, which tells you when you can start pumping over the next finished fermentation. Beer feed rate is a function of column size, alcohol content of the beer, capacity of the beer feed pump, and column temperatures, among other factors. For example, our column still will handle about 10-12 gallons of beer per minute, so it takes about 6-6.5 hours to process 4,000 gallons of beer, which makes 10-12 barrels. There are several important factors
relating to distillation for flavor and alcohol content, but from a production standpoint we want to limit any loss of alcohol in the “stillage” (beer after removal of alcohol). In a pot still setup there is typically a loss of between 0.3-1 percent ethanol in the stillage. Considering a mash of 18 percent brix that would make over 10 percent ABV, having 1 percent left over in the stillage is over 10 percent loss of your total production per batch. In a column still, you would expect less than 0.2 percent ABV in the stillage, and it is often undetectable according to data from several distilleries (Table 3). It doesn’t do any good to leave alcohol behind in the stillage, and that’s a major target area for improvement in many distilleries.
CONCLUDING REMARKS We have examined several important areas of the production process and how to manipulate each to achieve maximum batch turnover with minimum fermentation times. Superior grain quality and processing, efficient cook procedures, optimized fermentation, and distillation all can be tweaked to achieve desired results. With bourbon demands where they are today, it’s a great time to crank up production and make as much as your process will allow. Patrick Heist, Ph.D. is chief scientific officer of Ferm Solutions, Inc. and co-founder of Wilderness Trail Distillery. For more information visit www.ferm-solutions.net or call (859) 402-8707.
Cooper’s Select Barrels Our Cooper’s Select barrel uses 18-month seasoned staves, a process that changes the oak chemistry, adding complexity and softness to the palate. Learn more about our Cooper’s Select barrel by visiting our website.
www.iscbarrels.com Chad Spalding • 270.699.1557 firstname.lastname@example.org
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