Brewing with Coffee
One thing that you will find in common among professional brewers is that we usually drink more coffee throughout our day than we do beer. Some of us just need a caffeine fix to get us started on the right track for the day, while others are more connoisseurs in the coffee world. When it came time to design and make a coffee beer for the brewery I work at, I soon realized that coffee, as an ingredient, is no different than any other ingredient that you might put into your beer. It is an agricultural product that needs some attention to detail to hit your flavor targets. When making a recipe for a coffee beer of any style, the coffee addition should be made to showcase the coffee character while being supported by the base beer style. What may work for one recipe might not work for the same exact recipe when only changing the coffee variety or roasting level. By understanding coffee and all of its properties, a brewer can make the best decisions to brew a well-balanced beer that will showcase your coffee selection in your finished beer.
Base Beer Style
When we decide to make a coffee beer, we usually have a style of beer in mind that we would like to brew. The majority of the time it is a darker style beer such as a porter or stout, however do not let this discourage you from trying other styles. A coffee cream ale, lager, or even an IPA can taste just as delicious as any coffee porter or stout. Being able to successfully brew the base recipe with all of its minor variables (such as water profile, pH, fermentation, packaging, and other brewing processes) will help you build an excellent base for your coffee beer. Not all styles of beer are brewed in the same fashion or within the capabilities of all homebrewers. By picking a style that you are comfortable brewing and know much about will help you better formulate a recipe that will produce a perfect beer using what is available to you.
Remember, when making a coffee beer you want to showcase the coffee and roast level that is supported by this base beer style. Some brewers may think that brewing a beer with coffee in it is as simple as throwing a pot of coffee into a brew just before packaging. While this could produce a good beer, it likely will not produce a great beer. Knowing the base style and how to properly brew it along with the knowledge of coffee variety, roast, and most importantly how to apply it to your brewing practice will give you the best results.
Coffee
Coffee is a topic that we could go into great detail exploring every aspect of. It is just as in-depth as malting, growing hops, or any other aspect that goes into making a great beer. Being an agricultural product, the character of each coffee is dependent on the location, climate (which includes temperature and precipitation), soil composition, elevation, variety, and methods used to grow the coffee. These slight variations in variables will produce a noticeably different product, and because of this there is a high demand for select coffees.
As your average coffee drinker who never thought too much about coffee before using it in a beer, I got overwhelmed by the crash course I received on coffee. However, I will try to keep things simpler here. If you want more details there are entire books about the subject.
When you showcase coffee in your beer you are trying to incorporate as much of the coffee bean flavor without adding any harsh, unwanted attributes. Because coffee is a roasted product, acidity and balance is usually the main focus with coffee beers followed by flavor and aroma.
Where the coffee is grown has more effect on flavor than the specific variety. This is why we usually see the location instead of the variety in the name of the coffee when we buy it. There are a wide range of flavors that coffee can provide such as nutty, fruity, earthy, sweet, chocolaty, and herbal, to name a few.
Colombian varieties tend to be more sweet and less acidic than other varieties with some nutty notes. Brazilian coffee has a more chocolaty and creamier profile with an aftertaste that is not as clean as some Colombian varieties. African coffees, such as Ethiopian, are usually described as complex, fruity, and floral, and provide richer, full-bodied aromas and flavors. Asian coffees, like the famous Sumatra or Java varieties, tend to provide unique characteristics that can be more of an acquired taste. They are earthier, more complex, and darker than most other coffees, yet have a low acidity making them great for using in beer production.
Any coffee variety and roast level will work in a coffee beer — it just depends on what type of flavors, character, and intensity you want in your recipe. When looking for the right characteristics for your beer, you can either find what brand of coffee you enjoy the most, or you can visit your local coffee shop to experience some more detailed selections. If you call ahead or visit the coffee shop during slow business hours the staff are usually more than happy to take the time to explain coffee, their processes, and any suggestions of their products to better fit the profile you are seeking in your recipe.
How and When to Add the Coffee
In the world of homebrewing everything is possible, and everyone has their favorite methods with stories to tell on every topic. I, too, am no different. I have heard of everything ranging from adding the coffee into the mash, during sparging, all the way to adding it to a keg or cask. Some of the popular methods out there that I have heard of or done myself include: Adding a cheesecloth full of coffee (ground fine, ground coarse, or whole beans) near the end of boil until flameout, whirlpool additions, “dry bean” additions in the fermenter (fine, coarse, or whole beans, with and without cheesecloth bags), hot-brewed coffee added to the packaging vessel, cold-brewed coffee (soaked in water or beer) added to the packaging vessel, or just placing a cheesecloth bag with coffee beans (ground fine, coarse, or whole beans) inside a keg.
Whole Bean vs. Ground
I prefer using whole coffee beans over ground beans, coarse or fine. Roasted coffee beans are brittle and easier to handle and weigh when using whole beans, plus it helps keep the process consistent. Ground coffee beans will no doubt create a mess and have potential to clog up any equipment or filters. After a few batches using ground coffee I switched to whole beans and never went back. I personally have found no major flavor difference between using whole beans or ground coffee, however it is commonly stated that a finer grind will produce more intense characters than using a coarser grind or whole beans.
Hot-Side Additions
I do enjoy the simplicity of brewing up a strong pot of coffee and just pouring it into a keg or bottling bucket before packaging. This method has produced very acceptable beers in my experience, however it can also provide negative attributes to a finished beer. Using hot brewed coffee can easily extract acids, oils, tannins, as well as astringency from the coffee beans. Along with these undesired compounds, depending on the roast level of the coffee, it may off-balance your target roast character of the final beer.
I find this to also be true when using coffee anywhere on the hot side of the brewing process. If using any hot-side process, it is important to consider adjusting any roasted malt additions to account for those harsher attributes. I would advise against using any hot-side coffee additions due to the benefits of cold-side additions that will be discussed later.
If you are more on the adventurous side and still want to try using coffee during the hot side, then I would suggest adding the coffee towards the end of the boil. I have seen good results with additions at 15 minutes left in the boil, and many swear by whirlpool additions.
Cold-Side Additions
Cold brew/cold steep
For the reasons just mentioned, most brewers choose to do a cold-brewed coffee steep. Cold steeping provides more of the coffee bean flavor while adding a smoother coffee roast character without much of the harshness and acidity that you get from hot-side additions. A cold steep can be done by adding a cheesecloth bag of coffee to a container of cold water (or a sample of beer taken from the fermenter), and allowing it to sit at refrigerator temperatures (34–36 °F/1–2 °C) for 16–20 hours before adding the liquid to the packaging vessel. When doing this, remember to sanitize all jars and any utensils. For cold-brewed coffee it is suggested to use coarsely ground coffee, however for brewing I often use whole beans for simplicity and consistency. Each coffee variety and roast will produce different flavors so your cold steeping time will vary depending on desired flavor impact. Play around with it and find what you like. A benefit to making cold-brewed coffee is that you can steep the coffee for an exact amount of time before removing the coffee bags or decanting. This will help dial in the exact coffee profile you are trying to achieve. This precise cold-brewed coffee can then be saved for later use, however it is best to use as early as possible, so try to plan accordingly.
Dry Beaning
An alternative to the cold-brew steeping method would be to place the beans in a cheesecloth and use the dry hopping, or “dry beaning,” method in the fermenter. Steeping at fermentation temperatures can bring out pleasant coffee aromatics, but it will also have an easier time leaching the unwanted tannins and astringency if left for too long. I have found the best time to add the coffee is right at cold crashing. You don’t want to let the beer stay on the coffee beans for too long. For my taste, I’ve found three days at ~34 °F (1 °C) will produce the height of aromas that are really vibrant. Steeping the coffee longer will produce a richer but less complex coffee profile, and will be less vibrant. This applies for the cold-brewed method as well as for dry beaning.
I am not a fan of adding coffee during the hot-side of brewing because I feel that there is a higher risk of extracting tannins and astringency from the coffee beans. While this is personal perspective on this approach, I will say that I have tried beers from numerous homebrewers who used hot-side applications, and many were outstanding, especially the beers that used whirlpool additions after the heat was cut off.
Other specialty methods like adding espresso, making French-pressed coffee, brewing a pot of coffee, or even a double brew of hot coffee are all acceptable methods and will produce their own unique flavors. If you aren’t sure what approach to take, try many of them and taste the resulting differences firsthand.
Coffee Dosing Rate
Coffee addition rates can be almost at any range depending on what you are looking for, but here are some helpful tips that may guide you in deciding the dosing rate. Most coffee will provide 85 to 100 mg of caffeine per cup (8 oz./237 mL), depending on variety. Caffeine intoxication, which causes the “coffee shakes,” starts at 300 mg, so it might be wise not to exceed that. To make an 8 oz. (237 mL) cup of drinking coffee requires an average of 0.5 oz. (14 g) of ground coffee, which is equivalent to 60 g/L or 8 oz./gallon. Coffee variety and roast will directly affect the caffeine level, but should fall into the caffeine range of 85–100 mg.
A little bit can go a long way when brewing with coffee because most of the previously mentioned methods lead to the coffee being in contact with the wort or beer for an extended period of time compared to making a quick pot of coffee. At the brewery, for our coffee and cream stout, we do a coffee cold brew extract steep at a dosing rate of 0.82 ounce of whole bean coffee per gallon (6.1 g/L) of packageable beer. The overall coffee character is very much the focus of the beer, all while allowing the base beer to shine through and complement the coffee profile.
Malt, Unfermentable Sugars, and Residual Sweetness
Your base beer style should guide you in the right direction on what malts to choose in designing your recipe. The malt will provide you with fermentable sugars, but you may also want some residual sweetness to balance any roasted character from the coffee. This can come from your malt selection or by creating unfermentable dextrins through higher mashing temperatures. Build your malt profile around your coffee and how you want to support its character. For our coffee and cream stout we chose to replace the standard 2-row malt that we normally use with a bolder Munich malt to provide more malt complexity. English malts that provide a richer bready malt character might also be a better choice over standard American 2-row malted barley, but it all depends on what your desired target character is. Understand your malts, manufacturers, and what each will provide to your finished beer.
Many coffee drinkers enjoy some sugar and cream in their coffee, and coffee beer is usually no different. Using crystal malts will provide some residual sweetness to help balance out the bitterness from the coffee. Another favorite among brewers is to use lactose, which is an unfermentable sugar that produces a creamy sweetness. These unfermentable sugars can be used up to 10 to 15% of the grist bill. You could also choose a less attenuative yeast strain that would give you a higher finishing gravity and more sweetness.
Water
Beer Brewing Water
Even if you do not use salt additions it is extremely helpful to have a water report so that you know your base water mineral content, and more importantly your residual alkalinity (RA). As you roast coffee, and even malt, the product will start to become acidic. Being aware of your RA will allow you to formulate your recipe to not only hit proper mash pH, even when using high amounts of roasted malts, but to also account for the acidity of the coffee. This information will guide you in deciding on your best mash schedule to prevent the final beer from being too acidic and unbalanced. There are other things in your water report to look at such as calcium, chloride, and sulfate levels or ratios to enhance the perception of maltiness or hoppiness, however I feel that when using an already acidic coffee as an ingredient that the biggest concern is the water’s RA in relation to the base style. The RA ranges for styles are -60 to 60 for pale beers, 60 to 120 for copper/amber/reds, and 120 to 240+ for dark beers.
Water is a detailed topic, but this should help guide you in the right direction even if you are not using any salts.
Coffee Brewing Water
The same water chemistry theory applies to brewing coffee, but in this case we do not have other grains and mash pH to worry about. According to the Specialty Coffee Association the standards for minerals to brew a balanced coffee requires a total hardness of 50–175 ppm CaCO3, a carbonate hardness of 40–75 ppm CaCO3, and a pH of 6–8. This might help explain why some people add a pinch of salt to their coffee grounds when brewing a pot of coffee.
Mash
Because brewers often favor the sweeter additions to balance the bitterness from the coffee, brewers often choose a mash temperature on the higher range of 152–154 °F (67–68 °C) to produce unfermentable dextrins. You can use this technique in conjunction with using crystal malts and/or lactose additions to reach your target sweetness balance.
When brewing a dark beer, it is wise to know your residual RA in your water report. If the RA is in the lower range of 70 and below, then it might be beneficial to allow your base malts to do its main enzyme conversion mash, and add the dark malts during vorlauf, or recirculation. By doing this method the main enzyme conversion has already taken place, the mash pH is stable, and the additions of dark malts at this time will add to color and flavor. This will allow proper enzyme conversion in the mash without adding salts (like calcium carbonate) to keep the mash pH in the 5.2– 5.6 range.
Because coffee, which is naturally acidic, is being showcased, it is important to have your base beer chemistry dialed in to create a smoother and better balanced beer due to proper water and mash chemistry.
Hops
Unless you are brewing a coffee IPA, chances are that your main goal with the hop addition is just to balance out the beer to let the coffee take the spotlight. I have found the best approach is to use a clean bittering hop variety with high alpha acids (such as Hallertau Magnum) to provide a clean bitterness while not using much vegetative hop matter as you would with lower alpha acid varieties. For 6–8% ABV beers I have had great success targeting 40–50 IBUs that come entirely from first wort hop additions.
Yeast
The base beer style, yeast selection, fermentation temperature and schedule should all support the coffee character of your final beer. Knowing the yeast profile and what it will contribute to the final product will help guide you in making the right yeast selection. By choosing a less attenuative yeast strain it will leave more unfermented sugars providing sweetness to the final beer.
Carbonation
I personally love a great cask or even a nitro pour of a coffee beer, no matter the style. There is something magical about the cascading bubbles, rich fluffy foam, intense aromas, and silky mouthfeel that comes from a cask or nitro tap. If you are able to go this route, then that would be my suggestion. For the majority of homebrewers who don’t have these options readily available, I would recommend to bottle or keg condition the beer to allow for natural carbonation. I would also suggest targeting a slightly lower carbonation level of maybe 2.3 to 2.5 volumes of CO2 (vs. the average 2.5-2.6 volumes of CO2). This will allow for a lighter, creamier mouthfeel vs. a high effervescent carbonation level that you might expect with an IPA. I have found that by week 3 of room temperature conditioning you reach a perfect sweet spot.
Coffee Roasting at Home Using an Oven
1. Preheat the oven to 475–500 °F (246–260 °C)
2. Spread green coffee beans onto a pan to create a single layer.
3. Once the oven is at temperature, place the pan into the oven, and stir evenly about every 2 minutes.
4. The color of the coffee beans will start to turn from green to a light brown, then start to rapidly turn to darker shades.
5. Listen for the first crack, which sounds like popcorn popping. This is a warning to start paying attention for the second crack. Continue to roast.
6. The second crack will sound like it is sizzling. From this point forward you need to constantly monitor the level of roast that you desire. During this stage of the process everything happens extremely fast.
7. Once you pull the pan from the oven pour the roasted coffee into a metal colander to allow for rapid cooling to lock in the properties at that roast level. This also allows for the chaff, or coffee husk, to come off the bean.
8. Total time in the oven is roughly 10–15 minutes, depending on desired roast level.
