smyrnaquince
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The pre-boil gravity (before any fermentation) should only depend on the mash itself, i.e. the grains, the water volumes, and the mash temperature.
AFTER the mash and boil, changing the amount of Trub Loss into the fermenter should not affect the Est Pre-Boil Gravity, but it does in BS3!
To demonstrate this, I created the simplest recipe I could, using only BS3-supplied values: All-Grain 5 Gallon equipment, 10 pounds of Pale Ale Malt, Single Infusion 150 degree F mash. I kept the Boil Off the same throughout.
Below, Test 1 uses the default Trub Loss setting. Test 2, Test 3, and Test 4 adjust the Trub Loss downward, the Batch Size upward, and the Bottling/Fermentation Loss upward, so that all four recipes result in the same Est Bottling Vol. Note that the Est Pre-Boil Gravity and the Original Gravity change each time!
The pre-boil gravity should not be affected by the trub losses after the boil, but they are. I am pretty sure that this is a bug in the BS3 software.
Dave
AFTER the mash and boil, changing the amount of Trub Loss into the fermenter should not affect the Est Pre-Boil Gravity, but it does in BS3!
To demonstrate this, I created the simplest recipe I could, using only BS3-supplied values: All-Grain 5 Gallon equipment, 10 pounds of Pale Ale Malt, Single Infusion 150 degree F mash. I kept the Boil Off the same throughout.
Below, Test 1 uses the default Trub Loss setting. Test 2, Test 3, and Test 4 adjust the Trub Loss downward, the Batch Size upward, and the Bottling/Fermentation Loss upward, so that all four recipes result in the same Est Bottling Vol. Note that the Est Pre-Boil Gravity and the Original Gravity change each time!
Test 1 (default) | Test 2 | Test 3 | Test 4 | |
Est Pre-Boil Gravity (SG) | 1.047 | 1.044 | 1.042 | 1.041 |
Est Original Gravity (SG) | 1.053 | 1.050 | 1.048 | 1.046 |
Post Boil Vol (gal) | 5.99 | 5.99 | 5.99 | 5.99 |
Trub Loss (gal) | 0.75 | 0.50 | 0.25 | 0.00 |
Batch Size (gal) | 5.00 | 5.25 | 5.50 | 5.75 |
Bottling/Fermentation Loss (gal) | 0.40 | 0.65 | 0.90 | 1.15 |
Est Bottling Vol (gal) | 4.60 | 4.60 | 4.60 | 4.60 |
The pre-boil gravity should not be affected by the trub losses after the boil, but they are. I am pretty sure that this is a bug in the BS3 software.
Dave