Right on, Jason. Excellent choices on the Bocks.
Bock is a traditional, strong German lager style, not necessarily dark in color. They are distinguished by not only their strength, but also a sweet maltiness. Traditional German brewing techniques include a decoction mash, whereby the temperature of the mash is elevated in several steps by removing part of the mash, heating it and then returning it to the main mash. This technique develops tremendous depth of malt flavor, and can be easily discerned in the best German beers. Since they focus on displaying malt, Bocks are probably the best example of the melanoidins created by this process.
Doppelbocks like Jason recommends are the "biggest" examples of the style (and my favorites as well - especially the Paulaner). However, there are good pale bocks as well. I just can't think of any that are brewed in America off the top of my head.
It is an economic problem, really. Making lagers in general is more expensive because the fermentation takes longer and requires refrigeration. Consequently, you have probably noticed that most "craft" breweries focus on Ale styles rather than Lagers. Budmilloors beer factories still make lagers profitably largely because of not only economy of scale, but also because they require less of the basic ingredients (Bud is not very flavorful for a reason) and stretch their grain bill with less costly fermentables (rice and corn instead of barley).
Many of the American bocks that you see are not very good because they exist more as a marketing ploy rather than as a stylistic expression of the brewer. I don't know that I would recognize Shiner Bock as a "bock" in a blind tasting, for instance. The American brewing tradition came primarily from German immigrants, but post-prohibition economics dictated that marketing was more important than adherence to traditional styles and techniques. It is simply impossible to do decoction mashes in huge quantity, yet companies wanted to diversify their offerings - hence, let's call the "dark" beer our "bock".
In general, if you can get a Bock from a local craft brewer, it will probably be pretty close to style, but to me, nothing can compare to a fresh, carefully handled example from Deutschland.
Hey Mark, thanks for the tip on the Cognac! Keep those kinds of tidbits coming, please!
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