This malt-forward amber lager—popular as a seasonal in the United States for a few decades now—is directly inspired by the Bavarian märzenbier tradition of brewing in March for autumn festivals.
Style: This can be confusing, but here we’re not tackling the blond festbier they serve at today’s Oktoberfest. (For more on that, see “Oktoberfestbier: The World’s Most Famous Party Lager” beerandbrewing.com.) Instead, we’re focusing on what we in the States tend to call “Oktoberfest.” This is a low- to medium-strength lager of 5 to 6 percent ABV, amber in color, with a complex array of malt flavors on display; the hops are backstage, never poking their heads around the curtain. There are two important caveats: One, it should not be caramelly or butterscotchy—it should not be an excuse to let your diacetyl run wild—and two, it should not be sweet. The whole point is to consume it in substantial quantities, and for that we need a nice, dry finish. American examples lean toward toasty, and that’s fine, especially for those cool fall evenings. Hopping is for balance only, with moderate bitterness and little or no hop flavor or aroma. Especially after extended aging, these should be beautiful, brilliantly clear, jewel-tone beers.
Ingredients: Complex doesn’t have to mean complicated, and you can get malt complexity without a grist bill as long as your alpenhorn. All you need are two base malts and one specialty malt. Your base malts will be Munich and … not pilsner. I mean, you can use pilsner malt—and most do—but I find that it leads to an added sweetness that we don’t need. Instead, I use a 50/50 blend of Munich and Maris Otter. To that we add a portion of Caramunich I. The Maris Otter adds a complementary bready/biscuit note, meshing beautifully with the higher-kilned Munich, while the Caramunich adds a pronounced caramel aroma without much sweetness on the palate. If you opt for pilsner malt instead, you might find that it’s necessary to add some lighter character malts and crystals to build complexity—and those just end up adding more sweetness. For me, simpler is always better.
For hops, just add 26 IBUs of anything at the start of the boil; you can use German hops for authenticity, but the flavor impact is minimal. (I use Magnum, for what it’s worth.) Yeast selection matters more, as does managing your fermentation effectively. I find that the Bavarian Lager strain, Wyeast 2206, preserves the full malty flavor while also attenuating fully. White Labs WLP820 Oktoberfest Lager should give you comparable results.
Process: Producing good lager is challenging. Start with a healthy pitch rate, erring on the side of “more yeast.” Beyond that, control your fermentation temperature. Start cool at about 50°F (10°C) and hold there for two days, then increase gradually each day over about 10 days, allowing it to finish at ambient temperature. Why? To ensure a healthy diacetyl cleanup and scrounging-up of fermentable sugars. Then crash to near-freezing for natural clarification and conditioning; what remains should be fully attenuated, malt-complex, fairly bitter, dry, and drinkable. You can package before lagering; all it needs now is carbonation and time.