BOIL 60 min vs. 90 min

OK what is really the point of a 90 min boil vs. a 60 min I guess I just dont really see the point unless your goint to boil your hops longer but I never see that.
really all I need some help with this I am going to recreate a JZ recipe for a Hells Bock and its a 90 min (waste your brewing time) boil and I would like to get some feedback on the matter.
Cheers
JJ

If the hop additions all start at 60 then the extra boil time is most likely to boil off the excess volume in the kettle. Since you can't do that after you've started adding hops (changes the hop profile) you need to do it beforehand. It's also possible that they are trying to achieve a small amount of caramelization in kettle, but that I'm not too sure about.

Most of my boils are 70 minutes for example, that is how long it takes my setup to boil down the volume I always collect into my kettle.

I think in this one the importance of the 90 min boil is to drive off as much DMS as possible. This is especially true with grain bills with a lot of pilsner malt, probably the case with a helles.

He talks about this a lot on his show. It is also important (maybe more important) to drop your wort temp below 140 as fast as possible after the boil is done. He said he can get by with a 60 min boil with his wort chiller (below 140 in a minute).

The length of the boil beyond hop utilization and sanitation is really dependant on how long it takes to secure the hot break which ultimately assists in producing a clear stable beer. As long as this has fully occured it doesn't really matter how long you boil for as there isn't that much difference between a 60 and 90 min boil when it comes to utilization (especially considering no one calculation is actually correct.)

edit: you can judge when the hot break has occured by taking a sample, you should see flocks of protein that will start to settle once removed from the vigor of the boil. Worth a Read (Clicky)

Beerrific is correct. A 90 minute boil in this case is to drive off dms.

On bigger beers I end up with enough wort after sparge that I need at least 90 minutes to boil. Not that I need the time for bittering. The longest I've boiled hops is 75 min.

Not only might you need to boil off excess volume or get rid of dms(whatever that is) but won't the longer you boil the more a german malt profile you will create? Instead of doing decoctions you can just boil for 3 hours to get a similar malt profile. You will get a certain amount more carmelization with longer boil times. Maybe instead of just boiling off volume and getting rid of DMS that was another goal by a longer boil time?

Grimsawyer said:

Not only might you need to boil off excess volume or get rid of dms(whatever that is) but won't the longer you boil the more a german malt profile you will create? Instead of doing decoctions you can just boil for 3 hours to get a similar malt profile. You will get a certain amount more carmelization with longer boil times. Maybe instead of just boiling off volume and getting rid of DMS that was another goal by a longer boil time?

Click to expand...

I don't think boiling the wort longer is going to give the same end effects as a decoction. Similar? Maybe. But to get want you want from a decoction it is important to have the grain boil, at the lower pH of course. I have be doing some readings about decoction mashing and it may or may not add, it is somewhat interesting.

I'll opt for a 90 minute boil if using pils malt to drive off dms, sometimes longer for reduction and/or melanoidin formation.

Outside of this, it's 60 minutes.

OK first What is DMS???
second I guess I can see if reduction is in order!
BUT... if I can get 85% eff and still only do a 60 min boil is it safe to say I dont really need to do a 90 min boil.. again I am looking to do a hells bock. I just want to know if there is some MAGIC in there somewhere I am not seeing?
JJ

DMS= Dimethyl Sulfide, a cooked vegetable flavor that is not wanted. Corn contributes more than malt. Boiling drives it off.

The short answer on longer boils is that it gives a little more carmelization of the sugars than a regular 60 minute boil, developing the flavor and reducing the fermentability of the wort,...and driving off DMS.

Jaybird said:

OK first What is DMS???
second I guess I can see if reduction is in order!
BUT... if I can get 85% eff and still only do a 60 min boil is it safe to say I dont really need to do a 90 min boil.. again I am looking to do a hells bock. I just want to know if there is some MAGIC in there somewhere I am not seeing?
JJ

Click to expand...

Jaybird;

If you are using Pilsner malt (which would be the malt of choice for a helles) you need to do the longer boil. Pilsner malt has higher levels of S-methylmethionine then found in other base malts and is the precursor to DMS which is created by heat. A longer boil with the lid off combined with rapid chilling will reduce the amount of DMS in your wort and resulting off-flavour in your beer. Not magic, just brewing science in action...

Very good 411 guys thanks. I will shoot for a 90 min w/ the Helles and just see what becomes of it. again thanks for the tips
JJ

in a similar vein:

http://www.brewboard.com/index.php?showtopic=76187