Brewing Homemade Beer

Author & Photographer: Natalie Yaw

As a chemistry student at the University of Chicago, my education on the theoretical foundations of chemical processes has been robust.  Arrow pushing reaction mechanisms? Check. Schemes of catalytic cycles for cross-metathesis? Check.  But what eluded me was how I could apply this knowledge in practice, outside of the classroom—and preferably in a way that would impress my friends and reassure my family that this expensive diploma was worth it.  After extended study there seemed to only be one solution that was a practical use of chemistry that would not engender a potential felony charge: homebrewing beer. Extracting sugars and fermenting them to produce alcohol and carbon dioxide gas is a true test of a chemist; the timing, ingredients, and conditions must all be just right in order to synthesize the perfect brew.  Armed with my theoretical knowledge, I convinced some like-minded chemists to help make a lager that would make Alpha Delt jealous and my parents proud. Just call me the Beerfoot Contessa, and read on to find out how you too can put that degree to good use.

Ingredients:

  • Dry Malt Extract

  • 2 oz Cascadia cryo-hops

  • Yeast

  • 24 Oz honey

  • 8 oz dried orange peel

  • 3 fresh lemons

  • 4 cinnamon sticks

  • 8 oz sugar

  • Special Equipment

  • Fermenter

  • Fermentation lock

  • Bottle capper, bottle caps and 50 bottles

As befits research scientists, we hit the books to make sure we understood the theory behind the brewing process before we began.  Cliff notes: sugar is extracted from grains and boiled in water, hops and other flavoring agents are added, yeast is added, the fermenter is capped, and in two weeks, you have beer.  Simple. The special equipment needed is minimal- a fermenter, which is just a huge bucket with an air-tight lid; a fermentation lock, which allows gas to escape during the first fermentation phase; and a bottle capper.  We were able to get all of the equipment and ingredients we needed (and some last-minute advice) at the Pursuit Supply Company, a specialty homebrew store in Old Irving Park, and headed home with a six-gallon bucket, dry malt extract, hops, and bottling equipment.

Thus began the first stage—brew day.  

Before we began, we had to prep our workspace meticulously, cleaning everything that could come into contact with our final product. It cannot be emphasized enough how important it is that everything that touches the beer is sterilized.  Since the beer is being left alone to ferment for weeks, any contaminant introduced other than the desired yeast will also ferment—and not into a yummy alcohol. We ended up rinsing everything in a bleach solution and then boiling water—this included spoons, lids, pots, and pans.  This is a labor-intensive step but cannot be skipped. Only then were we ready to begin.

Immediately, we ran into some issues translating theory into practice.  We were making six gallons of beer, all of which were meant to be brewed at once.  Unfortunately, a large pot on a stovetop only fits one gallon, and when I asked my boss if we could use the much larger lab equipment he told me it would be an “OSHA violation”, so we had to get creative.  We decided to make two gallons of concentrate on the stovetop, and then dilute it with the remaining four gallons in the fermentation bucket.

Four gallons of filtered and boiled water were added to the fermentation bucket immediately.  The remaining two gallons were boiled on the stove and would become the ‘wort’ concentrate- the sugary flavored mixture that the yeast would feed on.  A true brewmaster would start from a burlap sack of grain and extract their own malt- about 6 pounds of sugary mash- but due to our aforementioned real-estate limitations, we took a shortcut popular among homebrewers and bought a dry malt extract.  This malt is what gives the beer its base characteristics- determining its classification as an ale, lager, porter, stout, etc.—and is dissolved first in the boiling water.

br1.jpg

We went with a pilsner base, because a light beer seemed less intimidating for our first brew, and were immediately proven wrong when the sugary water boiled over onto the stovetop and made a gigantic mess.  Lesson learned, we constantly stirred and monitored our wort for the next hour. The next step was to add any desired aromatics or flavors, which were to steep in the boiling water for 15-30 minutes, depending on how strong the flavors were.  

We opted to go for a citrusy profile-- staying true to our roots in an ode to the grapefruit distillation lab in second year organic chemistry--and prepped cheesecloth bags filled with cinnamon, lemon zest, and dried orange peel.  A separate bag was filled with the hops. The hops were added at the 30-minute mark and the citruses at the 15, and allowed to steep. When the hour was up, the wort had to be chilled as quickly as possible(you want to add the yeast quickly, but if the wort is too hot the yeast will be killed) so we rushed the pot outside and into a snowbank.

Once chilled, the wort was added to the fermenter along with the yeast and the honey.  The lid was sealed, the fermentation lock set up, and the wait began. Immediately, the fermentation lock began to bubble as the yeast went to work.  The fermentation lock is a small piece of plastic shaped like an ‘s’ and filled with water. It allows gas to escape the fermenter, but not enter it. This is important because it allows the yeast to ferment in a sanitary environment without overpressurizing.  Over the next two weeks, the gurgling died down, indicating that the first stage of fermentation was done.

It’s tempting to sneak a peek during this stage.  The bucket is making fun bubbling noises; you want to see what’s happening inside; you want to make sure you’re not growing mold; the spirit of fearless inquiry compels you.  But do not open the fermenter if you do not have to--it is just one more opportunity for contaminants to enter your beer!


We managed to resist the temptation and were rewarded two weeks later by opening up our bucket and finding warm, flat beer--exactly what you should have at this stage.  In order to introduce the carbonation, the beer is transferred into bottles and capped so the CO2 gas produced by the yeast is trapped.  Again, everything was sanitized thoroughly, including the bottles and bottle caps.  One cup of priming sugar was dissolved in water and stirred into the beer to reactivate the yeast. The beer was then funneled into bottles and capped.

After one more week of waiting- it was time to crack open some cold ones and share! Our pilsner was fruity, carbonated, and alcoholic- indicating the total success of our chemical reaction and our transcendence from theory into practice.  Repeated trials are necessary to confirm the results, of course, but we can rest easy knowing our degrees can indeed serve a practical purpose.

Melanie WangComment