I admit, I’m behind the times. While my friends are attending increasingly popular beer festivals and visiting the growing number of micro-breweries around the world, I can’t tell the difference between a lager and a stout. This means that not only am I the worst person to send to the bar, I’ve also never given much thought to what it takes to brew a great beer.

Unlike me, John Sheppard is a beer expert. As a bioprocessing professor at North Carolina State University, Sheppard spends much of his time in his lab (which could easily be confused for a miniature brewery) studying how to best grow and control yeast—the fungi that convert sugar into alcohol.