To some, April 7th is a day like any other, but around the world beer lovers and barflys are raising their pints in celebration of National Beer Day. On college campuses, beer seems to be consumed like water but how is beer made and why does Keystone taste so bad? Lecturer Dwayne Bershaw, food science, has the answer, and it lies in the complicated process of brewing.
According to Bershaw, the process starts with malting, where raw barley grains from the field are converted into malt. In essence, this process involves prematurely sprouting the barley by soaking it in water.
“[Soaking] causes it to break down its containers that hold the starch, and also causes it to produce enzymes that are necessary to break the starches up into sugars,” Bershaw said. “The barley kernel itself is actually producing the enzymes to break down its own starches, because it wants to use that starch to grow.”
According to Bershaw, the grain is quickly dried, preserving the starches and allowing for the enzymes to be collected. After the grains are dried and milled in a grinder, they are called malt, and are ready for the next stage, mashing.
Bershaw explained that mashing prepares the starches for fermentation. Because the starches are too long for the yeast to consume as-is, the enzymes from the malting process are used to break down the starches into shorter, simpler sugars.
Since this breakdown requires energy, the malt is boiled in a pot filled with water, with the rate of breakdown controlled by the temperature and time of boiling.
The resulting sweet liquid, called wort, is then further boiled. This is necessary for several reasons.
“One reason is to eliminate microbes so you’re not worried about bringing in a contamination microbe from the raw malt; the other reason boiling is important is to create bitter taste by using hops.” Bershaw said.
Bershaw explained that Hops, the flowers of the hop plant, gives beer its various characteristics, and influences how the beer looks, tastes, smells, and even feels.
According to Bershaw, the brewer’s use of hops, in both type and timing, can result in a wide variety of beers. The hops can be added in three places: at the beginning of the boiling step, near the end of the boiling step, and during or after fermentation.
If added near the beginning of the boiling step, the beer gains the bitterness of the hops, contrasting with the sweetness of the malt. Hops added near the end of the boil generate a smaller amount of bitterness, but also increases the aroma from the beer. This aroma, called “kettle-hop aroma,” gives the beer a grassy, herbal, almost vegetable-like scent – what we think of as the classic “beer” smell.
Additionally, the brewer can fine tune the drink with varying malt concentrations. If the brewer wants a darker beer, with a different taste, they use a mix of basic malt and specialty malt, a much darker malt produced by drying the barley for a longer time.
According to Bershaw, the mixing of different malted barleys is common, and it’s the balance that Bershaw describes as “an artistic expression of what the brewer is trying to bring across in the final beer.”
The variety of beer comes from both the quantity and type of grains. “Some beers use different grains than malted barley… for instance they use wheat as an ingredient that gives you a slightly different aroma and flavor in the beer that’s made,” Bershaw said.
Another variable the brewer can control is the alcohol content. “The amount of grain that you use and the amount of water that you use to cook the grain, has an impact on how much sugar you get in the solution before it’s fermented into alcohol; that is directly related to the alcohol content of the final beer,” Bershaw said.
A lighter beer usually means a lower alcohol content, but there are exceptions. Bershaw described one prominent example, the Belgian triple, which has a light, golden color but is 9 percent alcohol.
The temperature of the water and the time for which the barley is boiled in the water also impacts the breakup of starches. A longer boiling time at the right temperature can have a higher yield of short, simple sugars that yeast can consume. Boiling at a higher or lower temperature can create sugars that are still too long for yeast.
According to Bershaw, the greater the presence of the latter sugars, called limit dextrins, the heavier the beer feels in your stomach and the higher the caloric content. This explains why one or two heavy beers might make you feel full.
These factors all work together to affect how a beer tastes, smells, and feels, and brewers are always experimenting to craft the perfect beer with their own personal flair.