Not having tasted a true altbier (to the best of my knowledge) but have tasted professionally made bocks and dopplebocks, I was wondering how the two styles compare, how do they contrast? But more in the areas of taste and malts and hops? Anyone have an opinion?
Alts have a very firm bitterness backing up the malt backbone. They’re also a little lighter and havea bit more of a caramel flavor than the dark fruit of the bock.
As tom says alts have more hop presence than bocks do. Bocks generally have a very malt focused flavor and consistency. Alts are lighter, with some serious hoppiness(for a German beer)going on. I can (and have) sat and enjoyed alts for hours on end, bocks are really too heavy for me to session. And I’m not talking about the 8 or 9% ABV dopplebocks, in general for me bocks are heavy on my system, even the smaller helles bock or maibocks.
Alts are a pretty broad style, as well, from pale hoppy beers that you might be more apt to mistake for a Pale Ale than a Bock, to beers that have some resemblance to a Swarzbier or a Czech Tmavy (Dunkel). As others have said, in a very general sense, Alts are lower OG and ABV (except for a Sticke or Dopple Sticke), more bitter and often with more hop flavor, have a slightly different yeast character, and finish drier than a Bock.
Also, in the case of Dusseldorf Alts, Alts are made with ale yeast and bocks are lagers. There are some North German Alts that are made with lager yeast. Regardless, the two are very distinctive styles (alts and bocks) though you may find some similarities between Sticke Alt and Bock and Doppelsticke alt and Doppelbock. You would likely find more similarities between dunkle and alt than bock and alt.