I’ve taken a long hiatus as it’s been a very busy summer, but I’m back and I’m writing about two of my favorite things: science and beer.
It’s Beer Week here in the District meaning lots of good deals on good beers across the city. Yesterday, I attended a Victory Tap Takeover at Pizzeria Paradiso in Dupont and tried a couple of solid brews.
But where did they come from? In fact, where does all beer come from? A couple months ago, I was lucky enough to get a tour of the Goose Island Brewery in Chicago to learn the science of beer, step-by-step. Now, in honor of DC beer week–during which a few solid Midwestern breweries will be featured–here is the science of beer.
You may not have CO2 on the brain as you order the next round, but the brewing process is surprisingly scientific.
In fact, the process of yeast essentially eating the sugar in the brew to create CO2 and alcohol is just as constant as the not-so-scientific process of people drinking the beer to create slurred words and foggy memories.
According to Tom Korder, brewery operations manager at Goose Island Brewery in Chicago, Ill., it all begins with measuring the grain. The dry grain is milled to break apart husks from starches, then mixed with hot water in the mash mixer. The heat releases enzymes that break up starches into simple sugars that the yeast can consume, like glucose and maltose, and also break up proteins into simple amino acids instead of large chains.
These enzymes are as picky as you may be about your beer—they work best at a specific temperature, which affects the flavor and body of the beer. In order to get the enzymes to stop working, the temperature is raised even higher.
At this point in the brewing process, the beer is primarily sugar and needs to be more bitter. For the beer, this is done through the addition of hops while the beer is boiling, Korder said. Adding the hops at high heat changes the alpha acids naturally found in the hops to isoalpha acids, which are much more bitter, essentially giving the brewers more bang for their buck.
The beer is then swirled around, like what the bar might be doing around you on a rough night, to allow solids left over from the hops to settle out. Next filtered water, which plays a big role in the character of the beer, is added to the sugary liquid left behind. A pilsner, for example, is from the Czech Republic, where the water is very soft.
One of the most important aspects of brewing, according to Korder, is to not allow any oxygen to get in the beer, which can make the beer taste like wet cardboard—not the ideal after work drink. The only time oxygen is added to the beer in Goose Island’s brewing process is right before yeast is added, since it will consume the oxygen.
All the yeast is grown in a lab right at Goose Island, where colonies start out small and are cultured until there is enough to brew a whole batch. The lab also measures color, bitterness, pH and cloudiness. There are even microscopes so individual yeast cells in samples of beer can be counted. When yeast is first added, there are around 10 million yeast cells per milliliter of liquid, but they grow exponentially.
Beer then ferments for eight days before it is filtered, bottled, packaged and put on pallets to be shipped to your favorite drinking establishment. According to the government, the amount of beer actually in the bottle must be within 3 milliliters of what is advertised. So if a bottle that says it has 355 milliliters actually has 351 mL, it gets trashed. Just like you’d be if you drank it.