Whereas Kölsch looks like a lager type beer, its production with top-fermenting yeast actually makes it a cousin of the darker Altbier from the Düsseldorf area and the English ale style beers. Drinking a Kölsch on a warm summer's evening can be a pleasant experience throughout because it combines the hopsyness of a lager with the smoothness of a lager type beer. However, in order to avoid that smoothness from turning into sheer sluggishness, both storing and serving need to ensure that the beer comes to the discerning customer in top freshness. This is also one reason why Kölsch traditionally is served in small narrow 0,2 litre glasses -- this shape ensures best that the beer stays fresh and that the head doesn't collapse.
The small serving size is not very popular with many of the bigger and more tourist-oriented beer gardens on Cologne's Rhine promenade and Old Town because it means more work for the Köbesse (waiters) and ultimately higher labour costs. They have started to introduce larger glasses, measuring 0,3 and even 0,5 litres. Some brewery houses offer groups the choice of putting a "Pittermännchen" on their table -- a small keg -- so that everybody can draft their own beer straight from the keg.
Due to the above difficulties, getting a really great Kölsch is not as easy as it would seem to be. Some Kölsch beers that are already smoother in their character can turn into disastrous drinks when served in the wrong place at the wrong time. Should you get such a "Plörre" (German slang term for sluggish beer), it's best to leave straight and go to another place.
Like all beers, Kölsch is best from the tap, only those Kölsch that are styled more towards the herb side rather than the smooth one are acceptable out of the bottle.
Here are a few local brands and my comments on them:
Fresh-Herb variants
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Gaffel Kölsch -- probably the one with the most intensive taste. Good from the bottle. Greatest chance for a good one from the draft IMO
Früh Kölsch -- rather clear taste, not as hopsy as Gaffel, a bit steely. Good all-round Kölsch. The safest bet to choose if you aren't sure what to take
Sünner Kölsch -- a smaller brewery from the East Bank of the Rhine. Very good out of the bottle, sadly not that many places serving it from the draught
Smooth Variants
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Peters Kölsch -- very smooth beer. Very high danger to turn into a horribly sluggish drink. Don't order this one in a crowded place -- utter disaster awaits!!!
Küppers Kölsch -- largely available outside of the Rhineland, not really popular within the Rhineland itself. Probably with good reason.


