Efficiency

[UsernameTaken]

I have always felt my BIAB BH efficiency is very low in the 50's when you hear everyone talking about 70's and 80's!

But wonder if I am calculating it correctly?

For example, using this calculator - https://www.brewersfriend.com/brewhouse-efficiency/

- I mash 5kg of Pilsner in 28 litres of water
- I loose 2L to the grain
- I loose 2L to the boil
- I finish with a post boil gravity of 1.050 in 24 litres of wort

Then i transfer the 1.050 wort to a 17 litre cube.

- If I calculate my efficiency as 24 litres of 1.050 I get 77% Kettle Ending Efficiency
- If I calculate my efficiency as 17 litres of 1.050 I get 55% Brew House Efficiency

Which is the one everyone is talking about when they specify their efficiency?

 

[tj2204]

You're either mashing in too much water or using a cube that's too small if you're only transferring 17 of 24 litres finished wort.

BH efficiency is the 55% - if you're throwing out 7 litres you're essentially discarding that additional 22% efficiency.

 

[damoninja]

Discarding 7 litres? Jeez brew smaller or package bigger

 

[UsernameTaken]

These numbers were just to illustrate my issue.

But I do generally aim to leave 5 litres behind in my electric urn as thats what sits below the tap and I do not want to tilt the urn as it would collect the crap at the bottom?

 

[tj2204]

That's way too much to leave behind. I use an urn too and have fitted a 90° elbow with a barb on the end to act as a pickup tube to collect wort below the tap.

 

[UsernameTaken]

So how much do you leave behind?

 

[damoninja]

I would leave a few litres behind from a 50L batch, maybe 5L.

No harm in a little trub getting in your FV...

 

[MHB]

Short answer is "Enough" anything above the trub!
You're right to leave the trub in the kettle, that's where it belongs (in spite of what some will say), in commercial design 5-10% of the kettle volume would be expected, so for an end of boil volume 24L 10% would be 2.4L, 5% would be 1.2L. Somewhere in that range would be a good place to start. That gives you a knockout of 21.6-22.8L, better than you are getting and its free.
A pickup tube as above, or even syphoning or tilting the kettle (carefully) would all be possible, I used a bent 1/2" SS tube for years, the tube rested on the bottom and turned up so it wasn't pulling trub in... lots of options.
Mark

 

[MHB]

Knew it wouldn't take long, lots of known reasons for leaving the trub in the kettle (trub not wort), it isn't fermentable it brings nothing good to your beer - leave it in the kettle!
Mark

 

[tj2204]

Agree with MHB. I'd leave behind less than 2 litres, my beersmith profile is set to 2l loss to trub and chiller.

 

[Sidney Harbour-Bridge]

I run my trub through a coffe filter over a couple of days, boil to sterilize cool and add to the fermenter, freeze and use for the stater for the next brew or with wheat beers I can usually save and freeze 3 litres which is enough to prime a 22 litre brew.

 

[UsernameTaken]

Thanks guys, very helpful!

Cheers,
UNT

 

[nosco]

I thought trub was not calculated into the batch size in software? So then its not calculated into efficiency?

 

[Coodgee]

I run my trub through a coffe filter over a couple of days, boil to sterilize cool and add to the fermenter, freeze and use for the stater for the next brew or with wheat beers I can usually save and freeze 3 litres which is enough to prime a 22 litre brew.

wow that's frugal!

 

[Sidney Harbour-Bridge]

wow that's frugal!

Thanks, I am a tight arse Pome

 

[barabool]

Bit confused and happy to be corrected but if you have '77% Kettle Ending Efficiency' then it doesn't matter how much you stick in your cube. It matters how much you have in your kettle. If your calculations are all correct and count in all variable factors - then the viable amount of wort you flush away doesn't affect your 77% BH efficiency.
If you threw away all but 1lt - that wort would still be 77% BH efficiency.

 

[Danscraftbeer]

I calculate on the batch size. So a 40lt batch left with 4lt trub in the kettle. That doesn't get counted as 44lt kettle volume. Calculate efficiency as 40lt batch size Net volume.
I am frugal with my labored efforts so I will bottle that drained trub (leaving hop flowers behind etc) in 2 - 3lt apple juice bottles and cold crash it for say a week.
4lt trub gets me ~1.6 to 1.8lt very clear wort. I then do the home canning thing and pressure cook/can that wort. Frugal yep! Use them as starter wort ready to go. Marvel at how crystal clear it is in the jar etc.
Cant help myself. You go to all that trouble and effort to design/ customize your own malt it seems worthy of keeping rather than chucking it. When I get enough buildup of stored canned wort I have then made Bitsa/Mongrel mix brew that was superb. It doesn't seem like extra labor to me more like added efficiency of labor. No fussing with boiling starter worts in flasks anymore etc. Canned wort ready to go.
$0.02

 

[MHB]

I think we need a new rule - Anyone wanting to discuss "Efficiency" must read "Understanding Efficiency" in Braukaiser, then clearly define which efficiency they are talking about!
I like Kai's work, shame he has to make it all sound so complicated because its in silly units, metric makes brewmaths so much less confusing.
Mark

 

[manticle]

Knew it wouldn't take long, lots of known reasons for leaving the trub in the kettle (trub not wort), it isn't fermentable it brings nothing good to your beer - leave it in the kettle!
Mark

You obviously haven't been reading brulosophy.

Check out this exbeeriment: http//www.brulosophy.com/brewertakesshitinkettleandonlyoneintwelvetastersnotice/freebeer

 

[MHB]

Obviously not, nor planning on starting any time soon.
Get plenty of "baseless" opinions offered without going out of my way to find more.
Mark