Brewing Beer in the Laboratory: Grain Amylases and Yeast’s Sweet Tooth

Brewing beer provides a straightforward and robust laboratory counterpart to classroom discussions of fermentation, a staple of the biochemistry curriculum. An exercise is described that provides several connections between lecture and laboratory content. Students first extract fermentable carbohydrates from whole grains, then ferment these with brewer’s yeast. Refractive index, specific gravity, CO 2 evolution, and thin-layer chromatography are used as metrics of carbohydrate consumption. Instructors are thus provided a flexible toolkit for qualitative and quantitative analysis of both variable grain amylase activity and anaerobe fuel preferences.