A question of setup - OG and bitterness

Hi fellow brewers!

I am a great fan of Beersmith and I use it for all my all grain brewing, but there is one thing i can´t figure out.
Hopefully you can help me.

My brew setup gives me a 3 liter loss to trub before transferring my wort to the fermenter after cooling.
If I enter my recipe with a 28 liter batch and 75% brewhouse efficiency I get a different result regarding OG and bitterness as apposed to entering my recipe with 25 liter batch and 3 liters loss to trub (keeping brewhouse efficiancy at 75%). The mash efficiency in the latter setup increases to 84%.

My boiling volume is the same with both setups and my logic tells me that the amount of wort in the boiler should also be the same (28 liters) and hence the OG and bitterness should also be the same(?).

Where is my logic wrong? Any one got the answer for this?

Lasse

lassehans1 said:

My boiling volume is the same with both setups and my logic tells me that the amount of wort in the boiler should also be the same (28 liters) and hence the OG and bitterness should also be the same(?).

Click to expand...

BHE is a bit of a briar patch for many users of BeerSmith. For others, it's like grabbing the third rail. Brewhouse efficiency is simply the percentage total sugars available that actually get into the fermenter.

When setting up BeerSmith, it is best to set trub loss to zero. This makes mash efficiency the same as brewhouse. After you measure your yield into the fermenter, you'll enter that into BeerSmith. It will calculate your actual efficiency for you, losses and all.

Then modify your equipment profile:
[list type=decimal]
[*]Enter the actual fermenter volume as Batch Yield.
[*]Measure any remaining trub and wort loss, entering the total as Loss to Trub & Chiller.
[*]Enter the Measured Efficiency number from the Fermentation tab into the equipment Brewhouse Efficiency field.
[/list]
As a double check, your Post Boil volume should match closely with your actual measurement. BeerSmith's predictions should now closely match your real results.

Here is a working calculation for BHE. It's simple and direct and will get you into the ballpark for BeerSmith predictions.

BHE = (Sg x BV) / (Pg x GW)

BHE: Brew House Efficiency
Sg: Wort Specific Gravity, post chill (or post boil)
BV: Batch Volume, as measured in the fermenter
Pg: Potential gravity of grain (found by double clicking the ingredient, but 39 is a good starting number)
GW: Grain Weight

This formula simply divides the gravity points yielded into the fermenter by the total gravity point potential of grain (or extract or sugars) used.

As with all gravity calculations, the specific gravity 1.0 is dropped (1.040 becomes 40).

Thanks. Will try that.