How much do you leave in your boil kettle?

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Muz

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Just brewed today and I'm wondering how much everyone leaves in their boil kettle when they drain to the cube/fermentor?

I have a boil kettle with a pretty high valve outlet. I use a hop spider so I keep hops out of the wort when I'm draining it but there is always heaps of kettle trub at the bottom after chilling with my immersion chiller.

As a result of all the trub and the high outlet I usually leave ~2.5L of wort in the bottle of the kettle. I'm not scared of getting kettle trub in the fermenter. I've read on Brulosophy that having some in the fermenter is good for fermentation and can actually help with clarity. I'm just not sure if that means I should drain every last drop and not care about it at all or if I should still be trying to minimise it.

What do others do and what are your kettle losses like?

Cheers.
 
5-10% of the end of boil volume is pretty common, or standard in brewing texts if you prefer. Its going to depend a lot on the layout of your kettle and how good your whirlpool is, with really good design you can get that down under 5% even as low as 2-3%.

There are three main things in kettle trub Hop Debris, Hot Break and if you chill in the kettle Cold Break.
Brülosophy is totally not how to brew, I can't recall them ever saying about any part of the brewing process "this is really important and you need to do it", its always the opposite, according to them nothing matters.

I wouldn't be too worried if Hop Debris got into the fermenter, would do no more harm than hop matter from dry hopping. At worst its a bit messy and gives you more crud in the fermenter to leave behind.
Cold Break, again its fine in the fermenter (well unless there is so much that it smothers the yeast - you would need really crappy malt or lots of cheap adjunct but it can happen). Very large amounts can reduce the bitterness as Iso-Alpha acids do stick to it. Yes a certain amount is a vital yeast nutrient and is beneficial to the yeast and happy well feed yeast makes better beer.

Hot break is another matter entirely. If you study up even a little bit on brewing, you will see there are a few reasons why we boil a wort. One of them is to get rid of excess high molecular weight protein (hot break) there are no benefits to having any of this stuff in your finished beer and lots of downsides.

I think I've been posting this about once a week, its part of the learning resources for the introductory brewing certificate offered by the IBD (International Brewer and Distiller) its written by a professional brewer, brewing researcher and teacher, I would put a bit more weight on what it says than on the opinions of a bunch of dudes who think their pissed mates are quality control.
Mark
 

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Listen to so
Just brewed today and I'm wondering how much everyone leaves in their boil kettle when they drain to the cube/fermentor?

I have a boil kettle with a pretty high valve outlet. I use a hop spider so I keep hops out of the wort when I'm draining it but there is always heaps of kettle trub at the bottom after chilling with my immersion chiller.

As a result of all the trub and the high outlet I usually leave ~2.5L of wort in the bottle of the kettle. I'm not scared of getting kettle trub in the fermenter. I've read on Brulosophy that having some in the fermenter is good for fermentation and can actually help with clarity. I'm just not sure if that means I should drain every last drop and not care about it at all or if I should still be trying to minimise it.

What do others do and what are your kettle losses like?

Cheers.
Listen to sound advice.

MHB

Steve
 
On a three gallon batch probably a cup stays in the kettle.

I don't stress on break and some hop debris in my fermenter.

MO
 
You will get some of the cold break in the fermenter even though it looks clear draw some wort into a glass and put it in the fridge, the cold break then becomes visible, nothing to worry about there. All the rest leave in the kettle.
 
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