“I had never thought of brewing as a job opportunity,” says Laura Burns, a 33-year-old beer enthusiast with a doctorate in cellular biology from Vanderbilt University.

But in 2016, when she approached Great Central Brewing Company, then a startup completing a facility in the West Loop, the owners looked at her credentials and hired her. And why wouldn’t they? The building blocks of beer are yeast cells, and knowing how to manipulate them is key to perfecting the flavor of a brew.

Today, Burns is the brains behind more than a few of the favorite craft beers of Chicago’s cognoscenti — not just those released under the Great Central label but also ones from local outfits like Kinslahger, Maplewood, Sketchbook, and Begyle, which contract with Great Central to produce their beers in high volume. Those pleasing flavors of banana and pear in Great Central’s Hefeweizen? Burns says they come from minute variations in fermentation temperature, aeration, and other factors affecting the propagation and life cycle of a very specific strain of yeast. So does that curious note of bubblegum in certain IPAs, or those tropical notes in some American pale ales.

If all that sounds more like science than craft, so be it. After all, as Burns points out, “a brewery is a lab.”