What's the difference between 2' or 2" of trub?

[seanppp]

This is an academic question:

Would there be a difference between having 2" of trub at the bottom of fermenter carboy compared with having 2' of trub? As far as I can reason, the surface area that's in contact with the beer is the same, so the beer has no idea how many inches of trub are under it.

Is this correct?

 

[kh54s10]

2 inches vs 2 inches? Or 2 feet vs 2 inches? Well the surface area is the same. The amount of beer lost to 2 inches might be near a gallon. At 2 feet you would lose all 5 gallons in the trub.

I guess that you are exaggeration the difference for illustration. But the amount of trub should only affect the amount of loss and have little or no effect on taste.

 

[stpug]

About 22" if my math is correct

 

[KurtB]

There is beer mixed into the trub, so the surface area in 2 inches of trub is a lot less than the surface area in 24 inches of trub. If there was not beer mixed into the trub, the bottom of the bed of trub would be dry.

Does that make a difference in the taste of the beer? That is up for debate.

 

[biertourist]

About 22" if my math is correct

Beat me to it!

 

[RedBeardedBrewer]

There is beer mixed into the trub, so the surface area in 2 inches of trub is a lot less than the surface area in 24 inches of trub. If there was not beer mixed into the trub, the bottom of the bed of trub would be dry.

Does that make a difference in the taste of the beer? That is up for debate.

I agree with Kurt here. The top layer of trub isn't like a barrier that keeps the beer separate from the trub below. The smaller molecules are free
to move based on their concentration gradients from trub to beer. I would suspect it would make a difference in taste but that's just a guess.

 

[LKABrewer]

If you substitute 'trub' for 'oak chips', what difference would it make? A LOT! I have to assume that a beer sitting on 2' of trub will pick up more flavor from that trub.

 

[TheZymurgist]

If you substitute 'trub' for 'oak chips', what difference would it make? A LOT! I have to assume that a beer sitting on 2' of trub will pick up more flavor from that trub.

I'm sure there would be a risk of having a 'yeasty' character to the beer, but that could be avoided with cold crashing. You'd only see adverse effects from sitting on the trub for a really really long time, at least on a homebrew scale.

OP, why are you asking? It might help if we knew where you were headed.

 

[seanppp]

I'm sure there would be a risk of having a 'yeasty' character to the beer, but that could be avoided with cold crashing. You'd only see adverse effects from sitting on the trub for a really really long time, at least on a homebrew scale.

OP, why are you asking? It might help if we knew where you were headed.

I was just thinking about the fact that people say you want to get the beer off the trub, etc, but unless you filter you're always going to have a little bit of trub. So I was thinking, what does the beer above the trub care whether there is 1/8" or 8"? It can only see the trub that it is in contact with...

So basically, I was wondering why people imply that having *less* trub is important, rather than saying: either *no* trub or else it doesn't matter.

 

[Yooper]

At the homebrew level, it's not that significant. But one of the reasons commercial breweries drop the trub out of their conicals has do to with pressure, not the width. A huge conical has a lot of beer in it- which weighs a lot as well. The pressure forced onto the yeast cake can cause some flavor impacts, as the yeast cells rupture and autolyse.

At the homebrew level, I don't know if there would be a significant flavor impact from a short term on 2' of trub vs 2" of trub. Long term, there would be.