Half the recipe, and full boil

[timeasterday]

I have some extract kits that I got on sale and am interested in only doing half at a time. I did a 5-gallon batch previously and it will take me forever to drink all of that, so I will be doing some smaller batches to have a little variety. I'm wondering about water volume and questioning if I need to really boil for 60 minutes if I do a late addition of the extract. I know the hops typically need to boil 60 minutes for bittering but can I cut down the boil time and accept a little less bittering? Is there any reason why I would need to add any extract right at the beginning of the boil? I'm thinking about just putting it all towards the end. Anyone do something like this?

 

[timeasterday]

Disregard this. I think I have the answers I need.

 

[Brownalemikie]

IMO, less boil time will increase bitterness.

 

[timeasterday]

IMO, less boil time will increase bitterness.

Really? That seems contradictory to what I have read. And the IBU's certainly drop on BeerSmith.

 

[McKnuckle]

You are correct - bitterness increases with boil time. However, it also increases as the wort gravity decreases, so you will get more bitterness boiling in plain water than you will in wort.

 

[MedicBrew]

You are correct - bitterness increases with boil time. However, it also increases as the wort gravity decreases, so you will get more bitterness boiling in plain water than you will in wort.

More bitterness in plain water?... why don't we just boil our hops in a pot of water then?

This seems to be an issue ive found searching across forums and articles... no-one can decide what relationship hops have to the initial boil gravity vrs the late additions boil gravity.

 

[McKnuckle]

We don’t boil in plain water because that’s not how beer is made. It’s only an option with extract, which is a very recent product in the history of brewing.

The IBU formulae all use boil gravity as a factor. Yes, it’s very much imperfect, since gravity gradually increases during the boil. You could calculate every addition separately if you wanted, but it’s easier and very practical to just use initial pre-boil gravity for all additions, given the inherent lack of precision in the IBU calculation to begin with.

 

[Brownalemikie]

Really? That seems contradictory to what I have read. And the IBU's certainly drop on BeerSmith.

My reason for thinking this is that instructions for brewing Caribou Slobber brown ale tell you to add half the hops for the total 45 minute boil and add the other half of the hops during the last 15 minutes of the boil. Why add hops for the last 15 minutes of boil? Thanks in advance.

 

[McKnuckle]

Hops boiled for a total time of 15-20 minutes will add a lot of hop flavor, and moderate bitterness, to the beer. That time range is considered a "flavor addition."

The longer hops boil, the more they contribute only bitterness, not flavor or aroma. That's why people follow many different hop schedules when brewing - to accentuate the 3 different aspects of what hops offer (bitterness, flavor, aroma - in descending order of boil duration and temperature).