I did a double decoction on my first-ever Hefeweizen last year (this one
), and while it's cool to be able to say I've done one, I don't think I would do it again.
One of the much-debated topics re: decocting is why to bother with it when modern malts are so well modified. One aspect of the debate is the necessity of the protein rest, and my experience actually gave me a side in the debate: my Hef had absolutely terrible
head retention, and I'm pretty sure it's because I did an unnecessary protein rest; the purpose of the rest is to break down proteins, and proteins are responsible for head retention. Everything else about the beer (banana/clove taste, mouthfeel, color, turbidity, etc.) was great, but it would lose its head in less than a minute.
I'm going to re-brew the Hef this year and sub in a pound or so of melanoidin malt instead of decocting, to see once and for all whether the poor head retention was a fluke.