The temperatures are rising. It’s about to be summer. Your basement fermenting area is creeping out of the lager temperature range. You need a beer that can be fermented cool (but not cold), has some ester character (but not too much), and is both refreshing and meant to be consumed fresh. It’s time for ... KÖLSCH! Brew your Kölsch tomorrow and you can enjoy it in a few short weeks when it starts to get really hot out there. A better “lawnmower beer” doesn’t exist.
Style
Kölsch refers to the signature beers that are produced in and around Cologne (Köln), Germany. They are generally pale in color, delicate in flavor, low in alcohol, and refreshing. They are probably the best example of a “gateway” beer you can strive for. If you have a friend who’s considering taking the leap from macro lager to craft beer, Kölsch is a great style to test drive. The flavors are restrained, and you’re not at risk of burning anyone out on the bitterness or alcohol.
Kölsches have a light honey and grainy malt flavor, appropriately balanced bittering, and the aroma and flavor of good old German noble hops: flowers and herbs accented by some light apple or pear esters. This is a style that is characterized a bit by what it’s not—which is to say it isn’t the “Pils malt showcase” that Helles is, nor is it the liquid breadbox and spice cabinet that Weizen is, nor is it the fruity fireworks display that some American and Belgian pale styles are. You should have something that’s hoppier than a Helles, less malty and spicy than a Weizen, less bitter than an APA, and less complicated than a saison. Kölsch is the quiet person in the corner who doesn’t say much, but makes small and essential contributions to the conversation.
Ingredients
Kölsch allows for a lot of freedom and interpretation in the recipe. Most will use a combination of Pilsner and Vienna malts, with the balance tilting substantially toward the Pils (though mine is about a 60/40 split). Hopping is pretty straightforward as well—25 IBUs or so will almost always be plenty, and you might want to focus less on bitterness and more on flavor and aroma hops additions (though, again, the beer should not be aggressively hops-forward). The real fun in creating a Kölsch, unlike some other styles, is in the marginal elements that you might not adjust all that much in your everyday beers.
Let’s start with yeast. Kölsch can be made with almost any yeast strain, because as you’ll see in the process discussion below, you won’t be treating your yeast in the same old way. I like the Wyeast 1007 German Ale, which is the equivalent to White Labs WLP029 German Ale/Kölsch strain—it reliably contributes a limited ester profile and can ferment fully at almost any temperature. In fact, this is my workhorse yeast for all my non-Belgian ales and hybrids. Choose a strain that has a particular character you like, but make sure it isn’t one that is too temperature-sensitive (avoid many of the dedicated saison strains, for example).
Then take a look at your water. I know, this scares the hell out of a lot of brewers, but I assure you, there’s nothing to worry about. Kölsch (thanks to the groundwater chemistry in Cologne) tends to have a slightly mineral character in the finished beer. Unlike in an English bitter (when you should absolutely not try to mimic the so-hard-it-might-break-your-glass water quality of Burton-on-Trent), you actually do want to get a touch of that Cologne-water feel in your beer.
For those of you who have generally soft water, you might consider a very limited addition of gypsum and/or calcium chloride (I’m talking no more than 3–4 grams per 5 gallons (19 liters). For slightly hard water leave it be, at least until after you have brewed this beer a couple of times. When the bittering seems a little too harsh, even when you back off the IBUs, then your water might be too hard. If not, you’re probably fine.
For those of you who have generally hard water, you’ll want to dilute your tap water with distilled water to cut back on the hardness. What you want is water that’s soft enough to allow for a decent level of bittering without “bite,” but also a bit of calcium to brighten up the flavor. It can be a tough balance to strike, but it’s essential.
And the secret ingredient is…acidulated malt. I put 3 ounces (85 g) into the grist in a 5 gallon (19 l) batch. This is going to add a slight and wonderfully bright “zip” to the malt flavor—that little touch of lactic acid adds a nice lemony tartness. It will also aid in efficiency in the mash, speed up conversion, lighten the color of the beer, and buy you some flavor stability in the bottle or keg. Add it. You won’t be sorry.
Process
Since Kölsch is a “hybrid,” you want some light esterification, but not so much that it overwhelms the flavor profile. This is accomplished through a cooler-than-usual (if using an ale strain) or warmer-than-usual (if using a lager strain) fermentation. Essentially, whichever strain you choose, ferment this thing at 60°F (16°C). Otherwise, treat it like any other beer!
Two weeks should be plenty of time for primary fermentation, then package and drink. If you’re a real stickler for the guidelines, you’ll also want to aggressively fine this beer to get it as clear as possible as quickly as possible, so consider Irish moss in the boil as well as a good cold crash post-fermentation, and maybe even a gelatin addition.
In closing…
Kölsch is a classic world beer style for a reason. It’s an easy-drinking beer that’s restrained but still full of character, and it’s a beer you’ll want to have on hand all summer, every summer. And when your friend says, “Hey, I’ve never had a craft beer before,” you should get one of these into his/her hand ASAP, before the Double IPA folks get there. If you do, you’ll win over a craft-beer convert for life.
For another perspective on brewing Kölsches (and a recipe), see Homebrewing a Kölsch.
Prost!