Bock is the king of rich and malty German beers. A difficult but rewarding style for homebrewers, as the smooth, dense malt layers can be found nowhere else. Lagering is necessary for smoothness, as is the use of a good German Lager yeast, preferably one that highlights the malt character. Enjoying bock is easy, just pour it into a big, thick glass or stein, then sit back in the cushiest armchair you can find and prepare for a lot of sipping and sighing.
Classic traditional Bock is an amber/brownish colored beer with a strong body and alcohol content to match. The focus is entirely on the malty goodness of German-style malts, with the hops contributing only enough bitterness to keep the beer from tasting syrupy or cloying. The dark color comes from darker base malts, such as Munich malt, with the occasional use of darker specialty grains. If you’re brewing all-grain, a decoction mash with a high final temperature rest will help make a dense, dextrinous wort. Because bock is a high-gravity beer, it is common for the beer to take a longer time lagering than most, a couple of months is common.
This is a pale beer, also called Helles Bock, that displays more balance than the average traditional Bock. The pale color comes from the prominent use of Pilsner malt, which is far more gentle and light in flavor than the Munich and Vienna malts used in dark Bocks. Maibock commonly has some Munich-style malts in lower proportions, and so exhibits a subdued version of malt richness. In addition, Maibock often has more hops than a regular bock, which increases the briskness a bit. Still a focus for fine German malts, but with a lighter approach. The “Mai” means May in German, and so Maibock is often a seasonal brew first tapped in the spring.
An even bigger bock beer, with higher alcohol and more and deeper malt flavor. This beer famously started as nourishment for the Paulaner monks during their Lenten fast. It was later sold as “Salvator”, still available today. Many other brewers who attempt the style use “-ator” in the name of their beer as a homage. The Doppelbock beer is usually over 7% alcohol, with some examples soaring higher than 10%. The hops serve only to provide a bit of balance, and allow a sweet malty fullness to dominate. Bready, chocolate, and caramel flavors play over an exceptionally smooth and full body.
Eisbock is an unusual beer made with a special technique. A Bock or Doppelbock is fermented completely, lagered, and then placed in a below freezing environment. Though the high alcohol content will keep the beer from freezing even at very low temperatures, a portion of the liquid will freeze and separate out. This frozen portion will be mostly water; once it is removed the beer left behind will be concentrated in all respects. A higher alcohol content, even higher than can be achieved by normal yeast fermentation, is often the goal, but the flavors are intensified as well. Any off flavors will become even more unpleasant after concentration, but if you have a perfect, malty bock, the intensity of the beer will be heightened.