I love a good classic Rauchbier, don't get me wrong: but if I'm at a bar and I see a Piwo Grodziskie (Gratzer, to the Germans), I'm going to pass that Rauchbier right on by.
Gratzer (which we'll call it from now on, because I'm German and writing "Piwo Grodziskie" is time consuming) is another classic, historical style that was all but dead. Craft (and home) brewers have led its comeback, though, and this beer is one that's close to my heart. Gratzer was one of the first beers I had that really hooked my imagination. I'd tasted a small range of "good" beers up to that point, but nothing magical.
Then, one fall afternoon, my brother-in-law pulled out a bottle of this as we were sitting on his back deck, admiring the cool autumn weather and leaves. He opened it up, poured, and I did that thing we beer geeks do when we're surprised and excited with a beer: I took a sip, then looked with widening eyes at the glass, and then went back for more.
This is a beer you should know how to brew, and the good news is that it's pleasantly simple to brew and sessionably wonderful to drink.
STYLE
Gratzer is a low-ABV smoked wheat beer. It has a lot going on, flavor-wise, for so low-alcohol a beer, especially when we consider its recipe (one, maybe two malts, one hops addition, clean ale yeast). The aroma and flavor should both feature noticeable levels of grainy wheat, mild smoke (though you can go higher in darker versions, which we'll touch on below), and a slightly-elevated carbonation level that adds a nice, crisp bite on the palate.
As you might expect given the wheat-centric grist, the beer should have a dense, long-lasting, bright white head atop a pale body (SRM may range as low as 2); do not, though, make a hazy beer. This should be quite clear, despite the wheat. Bittering is modest in absolute terms, but still quite aggressive given the low gravity (20-35 IBUs, or a nearly 1:1 bittering-to-gravity ratio).
One final note on style: since that first Gratzer in the open air with Stan I've consumed a fair few of these beers. It is not monolithic in color, strength, or level of smoke. It is, though, consistently drinkable. Think of English Bitters and how they go down lightly and leave a bit of flinty mouthfeel behind, and you'll be well on your way to "getting" the spirit of this style, even if your recipe adds in more color or alcohol or secondary flavors than a "pure" Gratzer might.
RECIPE
This is a simple grist: Oak-smoked wheat malt, as much of it as you want to hit your target gravity (usually not more than 1.040, and I like to shoot for 1.038). That's it, unless you're going for a variation (more on those in a minute).
Hops are also simple: 28 IBUs of Hallertau, added at 20 minutes left in the boil. That's it. Some prefer the more herbal notes of Saaz or Tettnanger, but I like leaning on the floral, which to my palate is a better pairing with the smoke and wheat.
Finally, yeast: pick your favorite clean ale yeast. Mine is Wyeast 1007, German Ale, and if I get to the end of a brew day and have a few pounds of smoked malt leftover, there's a decent chance I'll turn out a quick batch of Gratzer, just because, and pitch 300-400ml of my yeast starter into it. 1007 is a real workhorse, and it can easily ferment this beer, even if underpitched.
Now, a note on variations: this is a great seasonal session beer. The hotter it is, the lighter you brew it; the colder it gets, the darker you can go. I recommend three basic variations. The recipe above is your "warm weather" Gratzer: simple, clean, pale. Then you have your "shoulder season" Gratzer, for fall and early spring: replace one pound of your grist with Munich malt, which will add a subtle level of rich toast.
Finally, the "Winter Gratzer": this is a closer cousin to my Rauchbier, with more-assertive smoke, thanks to swapping out a quarter of the Oak-smoked wheat malt for Cherry-smoked malt. Everything else stays the same. Voila: three recipes for the price of one.
PROCESS
Mash with about three-quarters of a pound of rice hulls to prevent sticking, at standard mashing temps (152F, for me). Boil, chill, and pitch as usual, then ferment at a straight 67F for a few days - it'll be fast. Don't rush it off the yeast, though: I had a batch of this with some residual acetaldehyde once, and although it was minimal it completely wrecked the flavor! Let it sit for a week to ten days, then cold crash and carbonate. I wouldn't go as high as I do for Berliner Weisse, but it should definitely be on the high side: 2.6 volumes of CO2 is a good target.
IN CLOSING
This is a beer that's going to make you look like a better brewer than you are. If you're new to this, especially if you're new to all-grain, brew it. Impress your friends and confound your enemies. Na zdorowie!