Wake Up and Smell the Coffee
Many brewers start their morning with a cup of coffee and end their evening with a glass of beer. It was only a matter of time before someone thought to combine the two. Back in 1995, Redhook introduced their Double Black Stout — a big, roasty stout with Starbucks coffee added. These days, many breweries and brewpubs produce coffee beers. There is even a coffee beer category at the GABF.
Perhaps the most interesting coffee beer in the world is Beer Geek Breakfast — Weasel. This beer, produced by the Danish brewery Mikkeller (but brewed at the Nøgne Ø brewery in Norway), is made with kopi luwak, an Indonesian coffee made from coffee “beans” that are eaten by the Asian Palm Civit (Paradoxurus hermaphroditus) — a housecat-sized mammal from the Order Carnivora. Kopi luwak producers collect the beans from the feces of these animals, clean and roast them.
Brewing a coffee beer — whether a straightforward espresso stout or something more exotic — is not difficult, but knowing a little bit about coffee can guide you toward making better decisions in your recipe formulation and brewing techniques.
Growing Coffee
Coffee beans typically come from one of two tropical trees, native to Africa — Coffea arabica and Coffea canephora. Other flavoring agents, especially chicory, have been used as a substitute for, or blended with, coffee.
- arabica yields the beans used to make “arabica” coffee, while C. canephra produces “robusta” beans. Arabica coffee is preferred by coffee experts over robusta for being less bitter and more aromatic. C. canephra is, however, more resistant to disease and produces higher yields. As such, it is cheaper to produce and often ends up in coffee blends. Robusta beans also contain roughly twice the caffeine as arabica.
Coffea trees produce small red fruits, similar to cherries, with two large seeds inside. These seeds are called coffee beans, even though coffee is not a legume. Prior to roasting, the seeds are called green beans.
Coffee is grown in an equatorial belt around the world extending from 25 degrees north latitude to 30 degrees south latitude, with most arabica grown at altitudes between 3,000 and 8,000 feet. Brazil is the world’s top coffee producer, producing about 25% of the world’s coffee. Other famous coffee growing regions include Guatemala, Costa Rica, Colombia, Ethiopia, Kenya, Yemen, Indonesia (including Java, whose name is sometimes used as a synonym for coffee) and Hawaii. Coffees from different regions have different characteristics, which may result from the botanical variety of coffee being grown, the environmental conditions the plants experience, the way the green beans are processed or a combination of these.
Green beans are prepared for roasting in a variety of ways, but they fall into two categories — dry and wet. The dry method basically involves picking the coffee cherries, then spreading them out in the sun to dry. The fruit pulp is removed mechanically after the fruits are dried. In the wet method, cherries are fermented to soften the flesh of the fruit before removing it and then drying the beans. There is a lot of variation in how coffee is processed. The main thing to remember is that in dry processing, the beans are dried, then the fruit pulp is removed. In the wet method, the fruit pulp is removed, and then the beans are dried. The wet method is used for most arabica coffees grown outside of Brazil. Almost all robusta coffees are dry processed. Once the green beans are ready, they are shipped to roasters.
Roasting Coffee Beans
The flavors and aroma of coffee are primarily developed during roasting, and are refined in the 24 hours after roasting. Coffee beans are generally roasted at 380–540 °F (193–282 °C) for up to 15 minutes. The internal temperature of the beans rises from their storage temperature to 375–425 °F (190–220 °C), with darker roasts finishing at higher temperatures. After roasting, the beans are cooled and allowed to rest for at least 24 hours before coffee is brewed from them. During this time period, referred to as degassing, carbon dioxide (CO2) formed during roasting is slowly released. There are a number of descriptive terms for the levels of roast and those most frequently encountered are summarized in Table 1. See the sidebar on page 35 for how to roast coffee at home.
Darker roasts feature the roasty and bitter flavors of the dark melanoidins developed during roasting while lighter roasts retain more of the varietal and location-specific aspects of the green beans. Many times, a particular kind of coffee is preferentially roasted to a specific level. For example, Hawaiian Kona coffee is generally lightly roasted. When you buy roasted beans, the region they were grown in and the level of roast is usually specified. For example, your coffee may be Sumatran Mandheling, Full City Roast.
Making a Cup of Coffee
There are many methods to making a cup of coffee. Basically, roasted coffee beans are ground and hot water is passed through them, but different methods utilize different water temperatures, grind fineness and contact times. Higher temperatures, finer grinds and longer extraction times favor more extraction, but also bring out excessive bitterness. In contrast, underextracted coffee is acidic and lacks body and sufficient roast character. Making a good cup of coffee requires the brewer to balance all of the variables to get just the right amount of extraction from the grounds.
Grinding — Most coffee sold in the United States is ground. However, many supermarkets or coffee specialty stores also sell roasted whole beans. There are a variety of appliances or gadgets for grinding coffee beans. The cheapest grinders utilize spinning blades to reduce the size of the beans. Burr grinders give the coffee brewer more control over the particle size of the grounds, but are more expensive. How finely the beans should be ground depends on the brewing method.
Extracting — The “recipe” for coffee is 15 parts water to every part coffee, by weight (approximately 2 tablespoons of medium ground coffee per 6.0 oz./180 mL of water). For a “regular” cup of coffee, about 1.3% of the liquid is coffee solids. The best coffee is made when just over 20% of the solids are extracted from the beans. Most coffee experts agree that the best coffee is made with a water temperature of 190–200 °F (85–93 °C) and a contact time of 1–3 minutes for finely ground beans or 6–8 minutes for coarsely ground beans.
Espresso is a strong coffee made by pushing pressurized (~9 PSI) hot water quickly through finely ground coffee beans; it contains about 5% solids. The key variables of different methods of coffee brewing are summarized in Table 2.
Old fashioned percolator coffee makers are not used much anymore, because the boiling water extracts too many coffee solids (up to 30% of the dry weight of the bean), drives off aromatic compounds and delivers an overly bitter cup.
Automatic drip coffee makers are popular, but vary widely in how close they come to the ideal brewing time and temperature. The Dutch company Technivorm specializes in producing coffee makers that deliver water at the right temperature and for the correct amount of time, and are approved by the Specialty Coffee Association of America. For manual drip coffee making, the all-glass Chemex coffee makers are a favorite of many coffee fans.
The French press method involves placing the ground coffee in a “plunger pot” and letting it steep in hot water. When the coffee is ready, the brewer pushes down on the plunger, forcing all the grounds to the bottom of the pot. The finished coffee is then poured from the pot. The French press method lets the coffee brewer control the time and temperature accurately, but leaves small bits of coffee solids behind in the beverage. Bitterness will continue to be extracted from these solids and can lead to excessive bitterness, but this generally isn’t a problem if the coffee is drank quickly. French presses are inexpensive and homebrewers can also use them to make hot water extracts from hops.
Machines that make espresso correctly (via pushing pressurized water through the grounds) are very expensive. Cheaper espresso machines use steam (at ambient pressure) to extract the coffee and — although they put a nice, frothy head on the cup — do not get the same results with regards to flavor.
As with beer, there are many variables to brewing good coffee and one cannot explain all the nuances of brewing coffee in a handful of paragraphs. Hopefully, however, understanding the basics of how a good cup of coffee is made will guide you in deciding how to incorporate coffee into your beer.
Coffee Flavor in Beer
Coffee has a complex flavor and aroma. We know that our taste buds only respond to five stimuli — sweet, sour, salty, bitter and umami (“brothy”). And we know that coffee is bitter and acidic. So, the bulk of what we think of as coffee flavor is really due to the vast number of volatile, aromatic oils in the cup. You can verify this for yourself with a simple experiment. Brew some coffee, pour a small amount in a cup (so it cools quickly), then go outside for a minute or two — or anywhere beyond the reach of the coffee’s aroma — and smell something strongly scented. Then, pinch your nose and quickly return and take a sip of the coffee. Don’t swish the coffee around in your mouth or sip so that you are pulling air across the surface of the brew and into your mouth. Just take a quick sip and swallow immediately. Next, quit pinching your nose, inhale the aroma of the coffee and take another sip. The first sip will likely taste bitter and acidic, but mono-dimensional. It may even be unpleasant. The second sip should taste like coffee; the bitterness and acidity will be present, but it will seem more complex. As beer brewers, this should tell us that, if we want the complex character of coffee in our beer — and not just “blank” bitterness and acidity — we should strive to preserve the aromatic compounds in the coffee.
Coffee in Beer
There are a variety of ways to add coffee to beer. These include adding ground beans (in a steeping sack) for the final few minutes of the boil or placing the grounds (again, in a steeping sack) in the post-boil wort prior to cooling. You can also add brewed coffee to the beer after primary fermentation or try “dry beaning” — adding whole beans to the secondary fermenter or keg and letting them steep in a manner analogous to dry hopping.
If you want to maximize the amount of coffee character you achieve with respect to the amount of coffee beans you use, adding brewed coffee after fermentation is the way to go. Using this method, you begin with coffee made with the right amount of extraction, and you don’t lose aromatics in the boil or fermentation. As an added benefit, you can make a small test blend before adding the coffee to the full batch of beer.
Making a small amount of coffee in a French press lets you control the temperature and contact time when brewing the coffee. You can also control the ratio of coffee to water in the mix. To keep the dilution of the beer to a minimum, making doubly or triply strong coffee is a good idea. Adding espresso would also be an excellent option. Make the coffee right before racking your beer to the keg or bottling bucket, add it to the vessel and rack the beer into it.
Boiling ground coffee or whole beans in wort is likely to lead to overextraction, even with short contact times, and many of the volatile aromas will evaporate. However, steeping coffee grounds immediately after the boil (just as many commercial brewers add hops to their whirlpool) is likely to produce good results, especially if you wait until the wort temperature drops below
200 °F (93 °C) and limit the contact time to an appropriate length, given how finely you ground the beans. Some volatiles will be lost during fermentation, but certainly not all of them. (You can still, for example, smell roasty aromas from darkly-roasted grains after a stout or porter wort has been boiled and fermented.)
“Dry beaning” will not extract as many oils as a hot extraction, but it does have the benefit that you can remove the coffee when the flavor reaches a satisfactory level.
A final method, used when a minimal amount of coffee character is desired, is to steep coffee beans overnight in cold water. This cold water extract is then added to the beer post-fermentation. A cold water coffee extract will be thin, fairly acidic and not show the degree of aroma that a regular cup of coffee would. It will have a fair amount of roast character, but not the strong bitterness of normal coffee. Making a cold-water extract would not be the way to go if you want an “in-your-face” coffee character, but it might be appropriate if you want just a hint of coffee without adding more bitterness to your beer. If you try this, taste the cold-brewed coffee critically before adding it to your beer. Don’t wreck a good beer with bad coffee.
Beer Styles, Coffee Character and Recipe Ideas
Most coffee beers combine the flavor of coffee with a beer style noted for its roasty character. Espresso stouts and coffee porters are popular types of coffee beers because the coffee adds some complexity to the roast character that is already present. If you have a stout or porter recipe you enjoy and brew regularly, you can easily make a small test blend and determine if brewing a whole batch of the coffee version would be worthwhile. Coffee adds bitterness, so you may want to dial down the hop bitterness or the amount of darkly roasted grains in a beer that is already very bitter or contains a lot of dark roast character.
Coffee can also be astringent, and it’s at least possible that dark beers (which are prone to being more astringent because of tannins from the dark grains) with coffee added could get too astringent. If you make a coffee beer and it seems “harsher” than it should — given the amount of hops, dark grains and coffee in the brew — consider trying to limit your astringency the next time to you brew it. Watching your pH and not oversparging will help minimize excess tannin extraction in the beer. The use of hard water to brew your coffee can tame its astringency.
The degree to which your coffee beans are roasted will, of course, influence the flavor of your coffee beer. The roast character from the coffee should complement the roast character in the beer. If I was making a coffee beer with a brown porter base, I would first explore using a lighter roast of coffee. For a robust porter — with more hop bitterness and sharper dark grain character — I think a darker roast is needed to stand up to the existing flavors. After the base beer is brewed, you can always do a test blend with a few different coffees, displaying different levels of roast, before you decide which to use. (This assumes you plan to add the coffee after fermentation).
Dark beers pair well with many “non-beer” flavors, and you may even want to consider making a beer with both coffee and some other flavor. Some possibilities include coffee and chocolate, coffee and cracker or biscuit-like flavors (from biscuit or Victory malt), coffee and fruit (such as raspberry) or coffee and smoke (from rauchmalz). Wolaver’s (the organic brand brewed by Otter Creek) makes a beer called Alta Gracia Coffee Porter — coffee porter with a hint of vanilla. Dave Green, who roasts the coffee for our Vermont office, spoke with Otter Creek’s Mike Gerhart and came up with the clone of this beer found later. The other recipe is a coffee beer based on a variation of my “house porter.”
If you enjoy a good cup of coffee, consider adding “the other brewed beverage” to your next batch of beer.
Home Roasting Coffee (By Dave Green)
Roast coffee at home . . . why? I would answer for the same reason we brew beer at home. It’s mainly about the enjoyment of taking a raw product and trying to produce a high quality finished version using your own tools. Or you could also justify it by saying you would be saving money, since raw coffee beans cost roughly half their roasted version. Either way, if you’d like to start home roasting coffee, you will need two things to start with — the raw coffee beans (also known as green beans) and some form of roasting device.
Green beans can be found at some of the better natural food stores, co-ops, homebrew shops or specialty coffee vendors, many of which can be found online. (See, for example, morecoffee.com or www.sweetmarias-.com) As the name implies, the beans will arrive the color green. They will also be much smaller than roasted beans and, of course, smelling nothing like the roasted product. There is a huge variety of green beans to explore from Tanzanian Peaberry to Mexican High Grown Chiapas to Sumatran Mandheling, just to name a few. Each coffee growing region lends its own distinctive characteristics and acidity to the mix.
Now that you have the green beans, you need to figure out how to roast them. You can go for the simple approach by utilizing a wok or skillet on a stovetop range and constantly stir the beans until a proper roast is gained. The next step up is to find an old air popcorn popper. The rotating roasting drum will provide a more even and consistent roast for the beans. (However, not all air popcorn poppers can be used to roast coffee beans). The ultimate tool for roasting beans at home is a home roaster. A coffee roaster will provide the consistent roast like the air popcorn popper, but will also permit the roaster to achieve different temperatures, adding an additional level of control over the finished product. Just as an all-grain brewer will mash grains at a range of temperatures to produce a different beer, the temperature profile of the roast will alter the final flavor of your home roasted coffee beans.
The actual roasting of the green beans can be done in as little as 4 minutes, but can take up to 30 minutes, depending on several factors. (Most commercially roasted beans are roasted in 9–14 minutes.) Typically, roasting occurs between roughly 400–500 °F (204–260 °C), so if you are planning a stovetop roast, you’ll probably want to have an oven or laser thermometer on hand to assure the proper temperature. Once you have achieved the proper temperature in the pan, you will want to stabilize the temperature while keeping the beans in constant motion to avoid scorching and keeping your ears open for the first crack of the beans. The sound of the first crack is something akin to a quiet pop of popcorn and you will see that the bean will start to yellow and expand as moisture trapped inside the bean looks for a way to escape. As the first crack ends, your beans will have reached a city roast, which is a medium roast. There is usually a short lull between cracks, but soon after the first crack finishes, you will start to hear the sharper cracks indicating that second crack has commenced; your beans have now reached a full city roast. The second crack indicates that the cellular matrix of the coffee is starting to break down. Chemical reactions inside the beans (including Maillard reactions and the caramelization of sugars) will begin to occur rapidly at this point, so it is important to be vigilant if you continue to roast past the start of the second crack. The beans can proceed through Vienna roast, into French roast and beyond fairly quickly. Smoke will start pouring out of the roast until finally the beans will start to ash or burn, so special attention is required through this phase.
Once you have reached the desired level of roast, you need to let the beans cool down. A colander is a good kitchen tool to utilize to help cool the beans fairly rapidly as the airflow will help dissipate heat faster. At this point, it is best to let the beans rest (degas) for about 24 hours to allow any trapped carbon dioxide (CO2) to escape from the bean. Store the beans in an airtight container out of direct sunlight. Roasted beans stay at peak freshness for roughly one week before the flavors and aromas begin to diminish.
One word of warning, roasting coffee beans produces copious amounts of smoke. Even if you have a smoke suppression system in your coffee roaster, you should still roast under a vent or hood, otherwise your smoke detector will go off. Outside roasting is preferred among many home coffee roasters.
Now that you know the basics, it’s time to give home coffee roasting a try. If you’re planning on adding coffee to your next batch of stout or porter, a nice full city roast is my preference. A full city roasted bean has nicely caramelized sugars, with a lot of the oils and soluble solids still intact to produce a flavorful complement to your homebrew.
Wolaver’s Alta Gracia Coffee Porter clone
(5 gallons/19 L, all-grain)
OG = 1.068 FG = 1.020
IBU = 27 SRM = 65 ABV = 6.2%
Ingredients
11.25 lbs. (5.1 kg) 2-row pale malt
1 lb. 3 oz. (0.54 kg) crystal malt (60 °L)
12 oz. (0.34 kg) chocolate malt (380 °L)
9 oz. (0.26 kg) white wheat malt
5.3 oz. (149 g) black malt (500 °L)
7.4 AAU Nugget hops (60 mins) (0.67 oz./20 g of 11% alpha acids)\
2.6 oz. (73 g) freshly roasted coffee (coarsely ground)
1⁄2 vanilla bean
White Labs WLP001 (California Ale), Wyeast 1056 (American Ale) or Safale Fermentis US-05 yeast
¾ cup corn sugar (if priming)
Step by Step
Mash at a liquor-to-grist ratio of 1.25 qt./lb. (2.6 L/kg). Mash temperature is 154 °F (68 °C). Boil for 60 minutes. Ferment at 68 °F (20 °C). Near the end of primary fermentation, take a small amount of beer and make an overnight cold extract from the coffee. Add coffee extract — liquid, coffee grounds and all — along with the vanilla bean, to the beer. Bottle or keg when fermentation is complete.
Extract with grains option:
Replace pale malt with 6.6 lbs. (3 kg) of light liquid malt extract, and 1.2 lbs. (0.54 kg) light dried malt extract. Steep grains in 1 gallon (3.8 L) of water at 154 °F (68 °C) for 45 minutes. Add water to make 3.0 gallons (11 L) of wort, add roughly half of the malt extract and boil for 60 minutes, adding hops at times indicated. Cool wort, transfer to fermenter and top up to 5.0 gallons (19 L). Aerate and pitch yeast. Ferment at 68 °F (20 °C). See all-grain recipe for how to add coffee and vanilla.
Duncan Hills Brutal Coffee Porter
(5 gallons/19 L, all-grain)
OG = 1.056 FG = 1.014
IBU = 35 SRM = 56+ ABV = 5.4%
Would you like a smooth-drinking porter with subtle coffee notes layered in between the roasted grain aromas? Then don’t even look at this recipe. If you like your coffee black, your porter robust and your death metal Swedish, then this your beer.
Ingredients
8 lbs. (3.6 kg) 2-row pale ale malt
2 lbs. (0.91 kg) Munich malt
14 oz. (0.40 kg) crystal malt (60 °L)
7 oz. (0.20 kg) chocolate malt
4 oz. (0.11 kg) black malt (500 °L)
4 oz. (0.11 kg) roasted barley (500 °L)
3 oz. (85 g) ground coffee (dark roast)
6 AAU Northern Brewer hops (60 mins) (0.67 oz./19 g of 9% alpha acids)
5 AAU First Gold hops (15 mins) (1 oz./28 g of 5% alpha acids)
0.5 oz. (14 g) First Gold hops (0 mins)
Wyeast 1968 (London ESB) or White Labs WLP002 (English Ale) yeast (1.5 qts./1.4 L yeast starter)
¾ cup corn sugar (if priming)
Step by Step
Mash at 154 °F (68 °C) for 60 minutes in 16 qts. (15 L) of water. Boil wort for 90 minutes, adding hops at times indicated. Ferment at 68 °F (20 °C). When you are ready to bottle or keg, coarsely grind 3.0 oz. (85 g) of dark roast coffee beans. Place in French press and add 200 °F (93 °C) water. Let grounds steep for 8 minutes, then pour coffee into keg or bottling bucket. Rack the beer into the coffee.
Extract with grains option:
Replace pale ale malt with 3.3 lbs. (1.5 kg) of light liquid malt extract, and 1.5 lbs. (0.68 kg) light dried malt extract. Place crushed grains in a large steeping bag and steep, in your brewpot, at 154 °F (68 °C) for 45 minutes. The volume of the steeping water should be 5.25 qts. (5.0 L). After steep, rinse grains with 2.0 qts (~2 L) of 170 F (77 C) water. Add water to make 3.0 gallons (11 L) of wort, add dried malt extract and boil for 60 minutes, adding hops at times indicated. Cool wort, transfer to fermenter and top up to 5.0 gallons (19 L). Aerate and pitch yeast. Ferment at 68 °F (20 °C). When you are ready to bottle or keg, see instructions in all-grain recipe for how to add coffee.
