[trentm]

Maybe you should have started your post with "I have this idea." The way your original post reads now, leads us to believe this is a common practice somewhere.

Your basic idea is to create a hop concentrated wort to blend with an existing beer that may be out of balance. The hopped batch could be fermented to completion and blended to taste for more controllable results. For it to work, I think you would need to add a large amount of hops. If not, your just diluting.

Many and various apologies for misleading you and then rest of the homebrewing world.

I had thought this was practiced by German homebrewers the world over, giving their beer that extra something.

Not even a hop concentrated wort just a first runnings boiled with some hops, not necessarily a lot of hops, not necessarily a little of hops.  Then added to a fermentation that's almost finished.  Fairly simplistic in practice but very powerful in aroma and flavor!?

[santoch]

Hanging on to wort after boiling for a few days is an invitation to infection.
Overnight, not really a problem.   The issue is that SOME microbes can make it into that wort after the boil.  Pitching the yeast builds an environment that is hostile and they become outnumbered by the yeast.  Leaving them without competition allows them to multiply if they are present.  This is a low probability but non-zero risk.

"Normal" krausening is done using successive batches to achieve similar intent but without the risks of holding out unfermented wort.  Otherwise, the differences are that both batches are (presumed) hopped identically, and you have the bigger added advantage that the new beer used to finish the old batch has vigorous, active yeast present.  By contrast, your hopped krausen approach adds new complex fermentables to a batch which has yeast that have neared cycle completion.  You _may_ get extra byproducts such as increased diacetyl, DMS, or other off flavors/aromas associated with weak fermentation by giving them more work to do on complex sugars (as opposed to simple fruit sugars, or Candi sugar, or priming sugar for comparison purposes).

I'm not saying it can't work.  I'm just pointing out some of the potential issues.

Try it and compare it with normal krausening and letting a batch go to completion without adding anything.  It would be a good experiment, I'd think.

My .02

[trentm]

Hanging on to wort after boiling for a few days is an invitation to infection.
Overnight, not really a problem.   The issue is that SOME microbes can make it into that wort after the boil.  Pitching the yeast builds an environment that is hostile and they become outnumbered by the yeast.  Leaving them without competition allows them to multiply if they are present.  This is a low probability but non-zero risk.

"Normal" krausening is done using successive batches to achieve similar intent but without the risks of holding out unfermented wort.  Otherwise, the differences are that both batches are (presumed) hopped identically, and you have the bigger added advantage that the new beer used to finish the old batch has vigorous, active yeast present.  By contrast, your hopped krausen approach adds new complex fermentables to a batch which has yeast that have neared cycle completion.  You _may_ get extra byproducts such as increased diacetyl, DMS, or other off flavors/aromas associated with weak fermentation by giving them more work to do on complex sugars (as opposed to simple fruit sugars, or Candi sugar, or priming sugar for comparison purposes).

I'm not saying it can't work.  I'm just pointing out some of the potential issues.

Try it and compare it with normal krausening and letting a batch go to completion without adding anything.  It would be a good experiment, I'd think.

My .02

I hear ya buddy.  Thought of all those things and the inherent risk of death by botulism.  Well, at least it's not the plague.

There are similar if not the same techniques in "high gravity" brewing such as demonstrated by Chris Colby:

http://byo.com/stout/item/137-american-pilsner-style-profile

Once wort comes to a boil, stir in 1/4 tsp of calcium chloride and then remove 1 gallon (3.8 L) of wort and place it in a covered pot to cool. This will be your kräusen wort you will use later. Once wort cools, siphon to a 1.0-gallon (3.8 L) jug and refrigerate until needed.
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Ferment beer at 52 °F (11 °C). When fermentation slows greatly, prepare kräusen beer. To do this, take the 1.0 gallon (3.8 L) of wort you reserved, add the kräusen hops and boil for 30 minutes, shooting for 0.75 gallons (2.8 L) of post-boil wort. Cool kräusen wort to 52 °F (11 °C), siphon to sanitized 1.0-gallon (3.8-L) jug, aerate and pitch with remaining yeast. Let kräusen beer begin fermenting and come to high kräusen. Add kräusen beer to main batch of beer and let fermentation finish at 52 °F (11 °C).

[majorvices]

Yeah, I don't understand this technique at all. When he said "hopped krausen" I guess I just thought he meant krausening from a hoppy beer. I'm still not sure what he is referring to.

Is the infamous "he" better than the infamous "they"?  Every now and then I'm summoned to the offices of the infamous "they".  It never turns out in their favor.

Then you haven't been in the right offices.

I have done krausening many times. It does a wonderful job of removing diacetyl or (sometimes) a stalled fermentation. But I can pretty much assure you that you aren't going to get some magical hop and malt flavor from this technique. Certainly is worth a shot though, look forward to hearing your perceptions.