How to reduce the volume of boil?

Hey all,

I'm curious as to what actually happens when you boil your wort. The reason I ask is because I have a large fermentor relative to my pot size, so I'm wondering if I can reduce the volume i'm boiling and make the same amount of beer. Or another way to put it, boil the same volume, but make more beer.

Right now, I do all grain and boil the full volume. Are there benefits to this method? Could I just boil a more concentrated liquor from my mash, and add that to preboiled/sterilized water in the fermenter?

Secondly, I now boil for 1 hour, but the only reason I know for doing it this long is because your bittering hop is supposed to be boiled for an hour. So if thats the only reason, could you boil your hops in a smaller volume of wort in a small side pot, then add it later? I realize you still want to boil your wort from the mash to sterilize it, but that could be done by boiling for 10 min or so, couldn't it?

As I write the above, another question comes to mind: I'm repeating a previous recipe for a pale ale, but I found it more bitter than I'd like. I'm planning on reducing the bittering hop I add, but what if I added the full amount with 45 min left to boil? how might that change the taste? And does this mean I can reduce my boil to 45 min?

For those that think I should just reduce the bittering hop amount, how much would be a good amount? Half?
(If it makes a difference, the hop additions are 3/4oz Northern Brewer (9%aa) for 60 min, 3/4oz Cascade (7%aa) for 30 min, 3/4oz Cascade (7%aa) for 15 min)

All input and opinions appreciated...

Hop utilization and boil volumes are not linear. The best advice I can give with so little space and time to type , is to get the book by Ray Daniels "Designing Great Beers". He has an excellant chapter on Hop utilization and some tables that you could use to determine your volumes and IBU's. It's funny how hop utilization differs when the gravity of wort is over 1.050. Boil times are critical for iso-alpha acid formation. Best I will give ...
buy the book. It will answer all your posted questions.

On page 64 of Randy Mosher's "Radical Brewing", there's a graph of hop utilization rates by boiling time and wort original gravity. A more experience brewer than myself could answer all of your questions using that graph it think.

Thanks for the responses. Looks like my library has the two books so I'll be checking them out soon.

But from your responses, am I right in assuming that the only point of boiling wort is hop utilization (and i guess sterilization of the wort)?

Boiling is not only for Hop utilization but also the coagulation of proteins.
This is part of the gunk left in the bottom of your kettle. 60 minutes is typical for hop utilization but 90 minute boils are recomended for better coagulation of grain proteins. You can do what your asking. The book Beer Captured has mini-mash recipes where they do just what you are suggesting. I do not think you can reduce the boil times though. You can reduce the volumes (increase wort concentration) and add additional water.

Hmmm.... can't seem to find that book anywhere... you sure thats what its called, Sudster?

Sorry , "Beer Captured" byTess and Mark Szamatulski.
ISBN# 0-9703442-5-2

Beer Captured is the best recipe book that I've found so far.

Wild

Keep in mind that it's all just basic chemistry when it comes to the ingredients, but when it comes to the boil, that's when the magic starts. Try not to mess around with the magic. It is that way simply because it is.

Stir and Mash
Boil and Bubble
Toss in a Toad
and make a Dubbel.

You are sooo poetic.