Boil times

[beerguy2009]

I am going to make the Sierra Nevada pale ale clone that was in the December 2012 issue of BYO magazine and it calls for a 90 minute boil adding the first hops at the beginning of the boil. What does that do different than a 60 minute boil which is what all my previous beers called for.

 

[WoodlandBrew]

Longer boil means more bitterness and less flavor from the hops. The tinseth equation models the bitter aspect of it pretty well.

 

[beerguy2009]

So is there a point when you max out on the bitterness you can get from the hops?

 

[WoodlandBrew]

So is there a point when you max out on the bitterness you can get from the hops?

The short answer is yes. At some point the Tinseth equation breaks down. 100 IBU is the top number I have heard, but I don't typically try to brew that high. Dog Fish Head makes an IPA that they say has 120 IBUs. At

 

[Calder]

Yes, you do reach a limit. Over 60 minutes you do not get much additional bitterness; point of diminishing returns.

A lot of times 90 minute boils is to drive off DMS. Required mostly for pilsner malts.

For anything other than pilsner malts, I don't believe you need a aything longer than 60 minutes. And that is to maximize the IBU extraction from the hops.

 

[Chadamus]

There is a beer called flying monkeys alpha fornication that is 2500 IBUs!
Different hops have different amounts that Isomerize at different boil lengths, so a longer boil allows for more possible buttering acids to be released. That's not to say you can't still have flavor and aroma though, hops added at or near the end of the boil, or dry hopped will still add the flavor and aroma!

 

[HopOnHops]

The preboil gravity should also be taken into account. If you want to make a big bitter thing, having high preboil volume with lower gravity will get you better hop utilization in addition to the extra boil time

 

[beerguy2009]

Yes, you do reach a limit. Over 60 minutes you do not get much additional bitterness; point of diminishing returns.

A lot of times 90 minute boils is to drive off DMS. Required mostly for pilsner malts.

For anything other than pilsner malts, I don't believe you need a aything longer than 60 minutes. And that is to maximize the IBU extraction from the hops.

So then why does the recipe in the issue call for a 90 minute boil? It has 2 row and carmel malt. There aren't any pilsner malts.