Presenter: John Eplett, MillerCoors.
As brewers, there is the expectation that if we deliver a consistent wort to our yeast the yeast in turn will deliver a consistent product. Personal experience tells otherwise. When something unexpected does happen, we go to the literature to find a cause and effect. Fortunately, there are a considerable number of publications that explain rate of cell growth, biomass increase, sulfur compound development, formation of flavor compounds, etc. The goal of the author is to tie together what has been published over the years back to actual operational experiences with regard to fermenter vessel aspect ratio and tank design, tank stratification, and CO2 generation. In addition, what is the impact of what is seen during fermentation with variations in wort gravity, wort aeration/oxygenation and trub carryover, wort cooling rate/temperature, and corresponding yeast pitching practices? This multitude of variables that a brewer is challenged with is then compounded by brewery design and layout. This raises the question of how to translate these “on the floor” experiences to the publications that can be easily assimilated by brewery and lab personnel. The outcome of this publication (presentation) will address the issues encountered in fermentation, the literature that explains what is experienced on the brewery floor, and what can be done to respond to or resolve these complex and trying issues.
Tom Eplett has been a member of MBAA since 1984. He served as president and on the Board Governors for MBAA District Western New York; he also served on the Board Governors for District Milwaukee and is the current by-laws chair. He started his brewing career in 1976 at the Miller Brewery in Fulton, NY, and has held numerous positions in quality and brewing at Fulton, Milwaukee, and MillerCoors Corporate. Tom is currently the senior staff brewer at the Eden, NC, brewery. He is a graduate of Bloomsburg University with B.S. degree in biological sciences, Syracuse University with an MBA, and has a diploma in brewing technology from the Siebel Institute, where he was the class valedictorian.