60 min vs 90 minute boils

[Dougie63]

I have recipes that want 60 and recipes that have 90 minute boils whats the difference taste in beer?

 

[RobWalker]

90 min boils are darker in colour I think...dunno what else it achieves!

 

[Revvy]

A 90 minute boil time is usually only done where there is Pilsner malt in the grainbill. It's done to drive off DMS precursors, which can cause a cooked corn flavor/aroma in beers. Longer boils are also done in big beers to concentrate the wort to drive up the gravity. They also could be done for hop utilization in really bitter beers.