Guide to Coffee Beers 

Experiments and Results of Different Methods to Infuse Beer with Coffee

C

offee lovers (myself included) can look a little foolish when it comes to the morning brew routine. The process generally starts by weighing out the beans, setting the correct grind size, hitting the desired brewing water temperature, and even timing the brew (some will treat the brewing water with minerals). I don’t claim to be an expert when it comes to coffee, but it has been another one of my obsessions over the years.

I think trying to maximize the coffee brewing experience has gotten me to be more critical when it comes to coffee beers. I love coffee beers, whether it’s a pale hoppy beer paired with a fruity light roast natural coffee or a dark beer paired with sweeter chocolate forward malts. I have two major complaints, however, with many of the coffee beers I drink. To my palate, they can either taste like a cup of coffee that’s been sitting out for too long or they can have an intense green pepper aroma/taste. What I’m looking for in a coffee beer is freshly brewed bright coffee flavor where the varietal and roast is paired nicely with the base beer. But, what’s the best way to go about getting this flavor? At Sapwood, we were lucky enough to team up Vigilante Coffee, my favorite DC area roaster and experimented with different coffee infusion methods and varietal selections and this post summarizes the results! 

I love the processes of brewing a cup coffee and like with brewing beer, I’ve spent a lot of time looking at other people’s equipment and processes, so for those interested, below is my current setup. What’s yours?!

My Coffee Setup and Routine 

• Heat up water to 210°F 99 (°C) ( Bonavita Gooseneck Kettle)
• Rinse the coffee filter with hot water and preheat carafe.
• Grind freshly roasted beans (Baratza Encore Conical Burr Grinder)
• Pour over (Kalita Wave 185)
• First bloom the coffee by pouring approximately 50 grams of water around the beans to allow the carbon dioxide to degas. (The fresher the roast, the more off-gassing).
• Drip into Carafe (Hiware 600ml Carafe)
• Pour over on a scale (Escali Primo P115C) (14 grams water to 1 gram coffee)
• Pour over should take approximately 3 minutes (adjust grind to achieve this, coarse grind equals faster brew time).

Coffee Beer Experiments 

Working with Vigilante’s head roaster Franklin Ventura, we made six different coffee beers to test out the following coffee and beer variables:

• Natural vs. Washed Coffee
• Cold Brew vs. Dry Beaning
• Same Day Roast vs. 1 Week After

We chose the different coffees by first doing a coffee cupping of all of the different varieties available at Vigilante. Coffee cupping is the standard method of evaluating coffee. It’s a fun process, and I found it extremely helpful in thinking deeper about the individual flavors in each coffee and how they might pair with a particular beer. After deciding on the different coffees and methods to infuse the beers, we held a private event at the brewery where Franklin and I led a tasting of the experiments and discussed our roast selections and infusion methods. This post goes through our trials and results and ends with a recipe we’ve come up with at Sapwood in collaboration with Vigilante for a beer called Bangun that incorporates our results! I was also lucky enough to get advice from an industry leading international coffee expert on coffee beers! 

Cold Brew vs. Dry Bean

For this experiment, we chose to use our beer named Conference Room 11, a 4.6% ABV lightly-hoppy wine-influenced wheat beer. The pale base beer was fermented with a blend of our house ale strain (RVA Manchester) and approximately 5% wine yeast (71B-1122) and dry-hopped on brew day lightly with Huell Melon hops. The result is a beer with mellow strawberry and cantaloupe flavors with low bitterness. We chose to pair the beer with a light roast called Mexico Gloria which has tasting notes of maple syrup and vanilla with flowery aromatics. Here we are interested in how a cold brew infusion will differ from a dry bean addition with the same coffee on the same base beer. 

Vigilante has found that about 16 hours of cold brew extraction is where the flavors seem to peak, so that’s the time frame we shot for both in this experiment and with the Bangun. For a 5-gallon batch, we used 4 ounces of coffee (coarsely ground in 1,200 mL water) for the cold brew beer and 2 ounces for 48 hours of contact time for the dry bean beer (dry beaning is essentially like dry hopping but with whole coffee beans). 

Results: The difference between the cold brew and dry beaned beer were fairly obvious to me. The cold brew beer had a much fainter coffee nose, but the coffee flavor was where it shined. The dry bean was the opposite, the aroma was big with a robust fruity coffee punch, but there was much less saturated coffee flavor. Just like how large whirlpool hop additions can help provide hop saturated flavor, it seems cold brew infusion helps to provide a coffee saturated flavor, but with less of the coffee shop aroma most might expect. The results inspired us to combine both methods in Bangun to try and get the best of both worlds.

Same Day Roast vs. 1 Week After 

The peak shelf life of coffee is relatively short, according to Franklin. Generally, coffee peaks around 3-4 days after it’s roasted and can start to go downhill after just ten days post-roast. Drinking coffee too early (first couple of days after it’s roasted) isn’t ideal because it doesn’t allow the coffee enough time to degas (allowing the carbon dioxide to escape from the beans) and can result in lackluster flavors that can come across flat and iron-like. The degassing from the beans is why coffee bags come with a one-way breathable valve, allowing carbon dioxide from the beans to escape the bag without oxygen getting in. 

Often skeptical that green pepper-like flavors in coffee beers is the result of using coffee that is past it’s prime and slightly oxidized, this experiment allowed us to test the same base beer dry beaned with either coffee roasted that very day to coffee roasted one week prior. Our theory is that coffee roasted the same day will degas in the beer, potentially preserving the fresh coffee flavors from having very little post-degassing time exposed to oxygen.

For this experiment, we chose to use our English-inspired Imperial oatmeal stout called Boom, Roasted! The base beer is rich, strong, and malty with intense chocolate, toffee, and subtle woody flavors. After doing a coffee cupping with the base beer in mind, we chose a dark roast coffee called El Fuego that should double down on the already present chocolate flavors and enhance the subtle roast notes. Both the beers were dry beaned at a rate of 2 ounces (56 grams) per 5-gallons for 48 hours in stainless dry hoppers.

Results: Tasting the beers blind confirmed our hypothesis. The coffee that was roasted and submerged in the beer the same day had a strong fresh coffee flavor that was super dark chocolate forward with a fun nutty edge. The beer that was roasted a week prior was noticeably different; here the aroma was much less rich and robust. There was a slight peppery note to the week-old roast, which was detected by many at the tasting. However, people’s opinions on which beer they liked more were split. I preferred the same day roast; to me, it had a stronger freshly brewed coffee flavor. The results here influenced the dry bean portion of the Bangun recipe below, we coordinated with Vigilante to make sure the coffee was roasted the same day we were ready to add the beans to beer!

Advice from Tim Wendelboe 

To add more than my sensory experience to this post, I reached out to Tim Wendelboe, owner of Tim Wendelboe, an espresso bar and coffee roastery in Oslo, Norway. Tim has won numerous awards for his coffees and is often credited for the rise in light roasts coffees now being roasted around the world. I’ve been a huge fan for a while, so it was a thrill to get Tim’s opinions for this post! According to Tim, the green pepper flavor from coffee can come from many things, especially if the coffee is underdeveloped or is a hybrid variety. Perhaps a better way to describe this stale coffee flavor is more of a stale anise/fennel seed flavor. Adding freshly roasted beans to beer does seem like a good way to get more of the “bready” notes from fresh coffee according to Tim, but the beans will be spending a long time degassing in the beer so this could make it more difficult to extract the coffee flavor. As the gas goes out of the bean, the beer will have a harder time getting in. This could mean that by attempting to preserve the fresh coffee flavor from same day roasts might result in longer whole bean contact time with the beer. For our trials, we needed at least 48 hours of contact to get the desired fresh coffee flavor we were after.

Tim suggests that adding whole coffee beans alone is a very poor way to extract coffee flavor into beer. In his experience, adding freshly grounded coffee to beer (in a dry hop-like fashion) resulted in a nice coffee flavor that was balanced and slightly sweet. Combining my experience with Tim’s advice, I wonder if adding coarsely ground fresh  coffee to beer post-fermentation along with same day roast whole beans might be a great way to get both fresh coffee aroma (whole beans) and flavor (coarse grinds). This could be an alternative approach to incorporating cold brew along with whole beans. I’d suggest starting with approximately 25% coarse grinds and 75% whole beans and taste the beer multiple times a day and be ready to keg or bottle the beer as soon as the coffee flavor is where you want it to be.  For a 5-gallon batch, this could look something like 2 ounces (56 grams) of whole beans and .5 ounces (14 grams) coarse ground coffee, likely for 24-48 hours of contact with the beer.

I asked Tim about the popular method of adding cold-brewed coffee to beer as a way to try an impart more saturated coffee flavor than you might get from just dry beaning alone. Interestingly, he’s not a big fan of cold-brewed coffee in general because this method misses out on a lot of volatile coffee aromas you get with heat extraction. He recommends brewing strong concentrated batches of cold brew if this method is used as not to dilute the beer too much. Tim has collaborated on a handful of coffee beers and has had great results when using espresso shots for flavor. But, making several hundred espresso shots is a tedious job for a big batch! This could be a great method for homebrew size batches, however. I’ve talked to brewers who incorporate this method by making espresso shots and immediately adding them to a vessel on ice as a way to preserve the fresh coffee aromatics, purging the head space with each addition of espresso to the vessel. They will then take that vessel and rack it into beer post-fermentation to taste after doing small test ratios.

The last bit of advice from Tim when it comes to making coffee beers (and this is something we employed with Bangun) is to avoid strong roasted and bitter malts in the base beer itself. You want the roast from the coffee additions alone to take the roast lead. It’s been my experience that adding coffee to a roast-heavy beer can quickly become too roast-forward (think burnt popcorn).

Natural vs. Washed Coffee

In my opinion, one of the most fun cups of coffee you can have is a light roast natural processes coffee. Descriptors of these kinds of coffee can range from wine-like aromatics to rich tropical fruit flavors that you wouldn’t typically associate with coffee. My understanding is that the natural process is one of the oldest ways to process coffee after it’s harvested. Here, the coffee cherry is dried then taken to a mill where the dry cherry and the husk is taken off the seeds. The natural process allows for longer contact with the fruit and sugars to go into the coffee seed, which can result in fruitier flavors. Washed coffee, on the other hand, the cherry and mucilage around the seed are removed first and put in water where fermentation removes the remaining flesh. After fermentation, the coffee is then dried, resulting in a truer taste of the coffee bean itself. The majority of coffee’s you purchase is going to be produced using the washed method.

We decided to put Rings of Light, our favorite low ABV 100% Citra hazy pale ale to the test with two different fruit-forward coffees (one natural and one washed). Although it might sound strange to pair a hoppy beer with coffee, when using fruity varietals, it can create some interesting flavors! For the coffees, we chose Vigilante’s José Daniel, a washed light roast coffee with descriptors of mango and crisp green apples compared to a natural Ethiopian called Chekata that has unique white peach and berry flavors. Both beers were dry beaned at a rate of 2 ounces (56 grams) per 5-gallons for 48 hours at 38°F. 

Results: Obviously, with two different coffees, the two beers are going to be noticeably different. The washed José Daniel Rings of Light was much more coffee-forward on the nose in terms of roast and chocolate flavors, which to me made the pale hoppy beer come across slightly malty. There was a strong green pepper flavor in the José Daniel beer that I found distracting (it was more than seven days post-roast). The natural Ethiopian Chekata Rings of Light was one of my favorites of the all the coffee beers of the night. The fruity coffee flavors combined with Citra created a candy-coffee thing that was super unique. This was the second time we added a fruity natural to a pale hoppy beer at Sapwood, both beers turned out great! In my opinion, when it comes to hop-forward beers, fruitier light roast coffees (especially naturals) pair best, there’s still a “coffee” flavor with the light roasts, but it doesn’t stomp all over the base beer like a darker roast might. 

Bangun Recipe

   Brewed: July 2019  

Results

As we designed the recipe for Bangun (which is Indonesian for wake up!) our intention was to create a summer coffee beer that drinks more like fresh cold brew coffee than a heavily roasted coffee stout. Because of this, we backed down on intense roasted malts and chose a base that beer that dances the line between an English brown ale and a porter. Using our experiment results above, we were inspired to combine both cold brew (for coffee saturated flavor) and dry beans (for fresh coffee aroma). Afraid of any oxidized coffee flavors, we timed our dry beaning so that we could add the beans the same day Franklin roasted them at Vigilante. Our method of dry beaning is similar to dry hopping, in this case we added the beans (in fine mesh bags) to the fermenter through the hop port while CO2 was being pumped through the spray ball to try and minimize oxygen uptake. We unitanked this beer, which means we fermented and carbonated in the same vessel. Homebrewers can easily add the coffee beans to a purged keg and rack the beer in. 

Results: I’m super happy with this beer! At just 5.6%, this beer can hit the spot on a hot summer day. The coffee aroma is intense, but fresh. I don’t get any of that green pepper aroma, which we think is a result of the same day roasting and dry beaning. There is a nice base layer of coffee flavors from the cold brew addition (which of the two varieties had a creamier mouthfeel, which made sense to use as part of the cold brew). The dry bean variety was slightly fruitier on the nose and more interesting to use as the aroma addition. Although we were tempted to use a dark roast for the beer, the test blends were over roasty. The medium roast Indonesian varieties used seem to provide enough roast to scream it’s a coffee beer, while not getting too acrid.

I’m a big fan of doing collaborations like this where two completely different skill sets come together! Not only did we learn a lot about coffee doing these two collaborations (coffee event and ultimately the big batch of Bangun) but leaning on the palate and experience of Franklin, I think we ended up with a much better beer!