Friday, May 15, 2009

Knock Out Hops

What are "knock out" hops? They are often referred to as 0min hops, and could even be considered "whirlpool" hops. In other words, these are hops that are added when the boil is finished and the heat turned off. I suppose each one could mean something slightly different, but all of them do the same thing...add lots of hop aroma to a beer. For the past year or so, I've been using this zero minute addition for an extra boost of aroma in certain styles.

Most of the time, published recipes call for this hop addition and is notated as 0min or KO. I used to add these hops at or even a little before the heat was cut. But I felt my beers just didn't have a bright enough hop scent, so I've redefined what this addition means to me and my beer.

I thought I might clarify what is written in all my recipes. When you see a 0min, or more often...KO addition, it doesn't mean they are added right when the heat is cut off. These hops are actually dropped in the hot wort after its been cooling for about 4-7 minutes. Why do I notate it like the books, I'm not quite sure? Maybe I'll start writing it as "-5min".

Adding hops while the wort is near boiling only scalds them and really diminishes their level of freshness in a brew's bouquet. Much like preparing french pressed coffee, the temperature of the water shouldn't be above 190°F, and even better at around 180°F, because anything higher tends to give my morning coffee a scalded & harsh flavor...yuck! This same theory applies to steeping tea, where boiling water should never be used. In the same fashion I add my "knock out" hops when the wort has cooled to about 180-170°F, or after the first chill water collection bucket is filled (about 5 minutes). The wort needs to be hot enough to breakdown the hops and offer a good hot steep, and if its too cool the hops tend to float on the surface without much contact.

I've also found that pellet hops give the best aroma for this addition. Primarily because they break down almost instantly, where as whole hops float and take much longer to get into full contact with the wort. It's all about contact time.

Just about all my beers that require a hop nose get this special post-KO addition. Especially if no dry hopping is planned, and a big hoppy presence is needed, a larger dosage of KO hops is infused.

8 comments:

SeƱor Brew™ said...

I'll have to try this. I usually add my knock out hops right after I turn off the burner. I'll see if I notice any difference by waiting 5 minutes. Of course a lot of beers that I use knock out hops for, I also dry hop, so the dry hopping aroma may overwhelm the knock out hop aroma anyway.

I'll try it anyway.

Bill said...

sigh ... I wish I had known this three hours ago. I made a Pilsner today with some KO hops in the recipe. I dumped 'em in after turning off the heat and before cooling. Lesson learned, I guess.

Bottled
Irish Stout
Espresso Porter

Fermenting
Polka Dot Pilsner (... with early KO hops)

Jake said...

Thats really interesting, I will definitely take this approach on my next beer with KO hops.

Ted Danyluk said...

Not sure if it's a lesson, but really something to experiment with. I think it's worth a try. It may not be very noticeable in the highly hopped ales, but it can really make a difference in beers that are balanced with a more delicate malt/hop relationship.

In hoppy beers, I like adding late hops, but space them out so that the last hop in the boil is around 10min-5min, and then leave the complete aroma hops in the KO.

I guess its all preference, and for me additions between 5min and flame-out have a bit of an off scent (can't really describe it). Could be just me. I guess I'd like to see the hops either boiled for some time, or not at all.

Slovak Brewer said...

I am going to try this with both beers I do tomorrow as they are recipe's I have done in some capacity. I always as my KO hops right as the flame is off and the chiller is running.

Ted Danyluk said...

That's great. It's cool to see some folks interested in tweaking recipes with a slightly different approach to flame out hops. I'm curious to hear anyone's thoughts after trying this.

The Wife said...

Dude, where do you learn all this stuff???

This is all Greek to me.

*secretly beaming with pride even though she has no idea what her husband is talking about*

Slovak Brewer said...

Ted, I mention your blog in the following post. Check it out.. http://freshbrewlog.blogspot.com/2009/05/things-i-have-been-doing-differently-or.html