Boiling for so long

[Cellar_Rat]

Is boiling just for hop oil extraction?

The reason I ask is I am looking at the all brewing steps and have to wonder if the actual 'rolling boil' time could be reduced particularly as I am now adopting the 'let it cool overnight' method rather than a 'chiller coil' method.

In my last brew I proved that hop extraction continues after rolling boil with this method

So me thinks: Boil for say 10 mins - turn off - insulate - remove hop bag after 2 hours.

Thoughts?

[joelw94]

I've brewed a few beers and have done a fair bit of reading on it. The conventional wisdom is that this would be a bad idea, boiling is to achieve more than extraction of bittering hops. The biggest dangers of such a short boil would be that you wouldn't boil off compounds in the malt that can sometimes cause serious off flavours, such as DMS, which gives your beer a strong cabbage or cooked corn flavour. It's also about achieving the 'hot break' to cause the proteins to drop out of the wort, a short boil is likely to give you very hazy beer unable to be cleared by fining. That said I've never tried such a short boil as that with a batch using all grain or a partial mash myself. If you were going to shorten the boil I'd do at least 30 mins, including your bittering addition as a boil is much more effective at isomerising alpha acids, although it will continue while your wort is slowly cooling, with no-chill I read to treat all your hop additions as if you put them in the boil for an extra 10 minutes. You're right about your aroma addition, to keep maximum hop flavour/aroma add it to the wort after it's cooled down a bit.