What is the knockout?

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rdwj

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I was looking through Palmer's book and noticed that in some recipes, he instructs you to add extract after the knockout. I looked in the glossary and didn't see a definition for the term. What does he mean??
 
Flame-out. The end of the boil. Aroma Hops are generally added at the end of the boil. I have never seen extract added at the end of the boil. The whole purpose of the boil is to sanitize the extract and drop protein.
 
I imagine the purpose would be to avoid carmelisation and darkening of the extract. As long as it's steeping in the boiling wort for about 15 minutes after you stop boiling I dont see a problem with sanitation.
 
I recently brewed a Kolsch, 2nd attempt, and I added extract late (30min) into the boil and it appears much lighter than the first time I boiled the same recipe when I added extract at the beginning. As long as you allow time for sanitizing it should work fine.
 
dougjones31 said:
Flame-out. The end of the boil. Aroma Hops are generally added at the end of the boil. I have never seen extract added at the end of the boil. The whole purpose of the boil is to sanitize the extract and drop protein.

Yep, just double checked. He has half of the extract being added at boil and half at knockout. Seems strange to me. I've seen the add late in the boil method, but after it's off the flame seems a bit odd.

Has anyone done one of these recipes???
 
rdwj said:
I was looking through Palmer's book and noticed that in some recipes, he instructs you to add extract after the knockout. I looked in the glossary and didn't see a definition for the term. What does he mean??

Charlie said "knock you out".
I'm gonna knock you out.
Charlie said knock you out...

(My apologies to LL)
 
You know... it is interesting that it's a common word, but don't seem to be in glossaries or what not....
 
Adding extract after the flame is out may indeed kill any germs if you let it sit hot for a while, but you will never get the protein to drop out of suspension unless you boil it. It may yeild a lighter brew, but it is sure to be cloudy beer. Chill haze will be a *****.
 
Mykel Obvious said:
I've never made any of the recipes, but John posts to the Brew Board in the Beer Forum... I'd post a question to him if I were you...

Great suggestion! He answered very quickly!!

Wow - how cool!


Yes, I meant flame-out. To reinterate: the idea is that you avoid a prolonged high gravity boil, which improves your hop utilizaiton and decreases maillard reactions that lead to wort darkening and extract twang off-flavors.
You don't necessarily have to turn the burner off and not boil the extract (you can boil it a short time if you want to), the idea is that merely heating it to pasteurization temperatures for a couple minutes is sufficient to sanitize the extract before cooling and pitching. I said 10 minutes in the book (p. 213), which is conservative to the point of being excessive. Earlier in Chapter 7, p. 82, I say at 5 minutes before the end of the boil.
So, in conlcusion, anytime at the end of the boil, for a couple minutes is sufficient. I should have been more clear in the book. Oh well, next time.

As an example, Milk is pastuerized by heating to 160F for at least 15 seconds.
Not pasteurizing the extract will not hurt you, but the beer fermentation could suffer from beer-spoilage bacteria or wild yeasts, which are probably not desired.
 
I have used recipes from local HBS which calls for boiling bittering hops for 45 minutes, remove from heat, add malt extract and then boil 15 minutes (with flavor hops and aroma hops at appropriate times). By contrast, the recipes from Austin and Midwest have the extract in the full 60 minute boil. I did notice an obvious chill haze with the local HBS that did not occur with the 60 minute boil. Both yeilded good tasting beer. But hey, we all like good tasting and clear beer! The chill haze comment seems to be valid.
 
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