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10-11-2013, 05:19 PM   #21
ajf
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Quote:
 Originally Posted by FatDragon Hmm, I see. The BIAB volume calculator that someone linked several posts ago gives numbers like this: Pre-Boil Volume needed: 4.52 gallons Absorption Loss: 0.77 gallons Boil Loss: 0.50 gallons Final Batch Size: 3.25 gallons So I was getting my "pre-boil volume equals the volume of liquid (not counting volume of the grain solids) before the grain bag is removed" definition from that, where they're clearly calculating the water that is absorbed in the grain as part of the pre-boil volume. I guess as long as the numbers are right, the terminology is secondary. What would the term be for "volume of liquid after mashing but before removing the grain bag" (what I was calling "pre-boil volume"), or does it even really matter?
The "volume of liquid after mashing but before removing the grain bag" is normally referred to as the "space required". The only time it matters is if you take a gravity reading prior to the boil, to calculate the amount of extra fermentables to add during the boil to achieve the desired gravity.

-a.

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10-11-2013, 06:27 PM   #22
Carlscan26
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Quote:
 Originally Posted by ajf The "volume of liquid after mashing but before removing the grain bag" is normally referred to as the "space required". The only time it matters is if you take a gravity reading prior to the boil, to calculate the amount of extra fermentables to add during the boil to achieve the desired gravity. -a.
Wouldn't you want the volume without the grains since you wouldn't be boiling with the grains in the pot?
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10-12-2013, 12:04 AM   #23
ajf
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Yes you would.
Perhaps I should have said that for such a calculation, you need the true pre-boil volume, and not the space (or volume) required.

-a.

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