Changing boil time in Beersmith2 does not effect gravity.

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kiwipen

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I just noticed this when editing a recipe. Changing the boil time does nothing to the estimated OG. 1 minute and 100 minutes gives the same result.
It does however change the estimated bitterness.

Changing brewhouse efficiency changes the Est. OG.

Is it supposed to be like that or have I messed up some settings?
 

wepeeler

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You might have to manually put in boil off rate. I used to use Beersmith but have since moved onto BrewersFriend. Should be under Equipment Profiles. Boiling longer will decrease your final volume, which in turn will increase your OG.
 
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kiwipen

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I have one 60 minute and one 90 minute profile of the same equipment.
Are there any obvious mistakes here that I'm not seeing?

GF60.jpg
GF90.jpg
 

doogster

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Hi -
Just checked this in BS3. And see the same behavior.

Here is what is happening: Your recipe has a target volume, or Batch Size (i.e. you are going to end up with the same amount of wort post boil / into your fermenter). Everything is based on this. So if you increase boil time, Beersmith changes the starting water volumes to compensate. The longer your boil, the more you boil off... so to end up at the same finishing volume, the starting water volumes must be increased. This LOWERS the pre-boil gravity due to dilution, but after you boil for the extended period... and up at your target post boil volume... the post boil gravity will always be the same.

Hope this helps.
 
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wepeeler

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Looks like starting boil volume is different in each profile, but they are utilizing the same boil off rate to give you the same final volume. That's why it's giving you the same OG. As @doogster said, BS is compensating for your longer boil by adding more to the initial volume.
 
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kiwipen

kiwipen

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Thank you guys for the help.

If I understand this correctly I could decrease my batch volume by 1,5 liter if I go from a 60 minute to a 90 minute boil and get the results I was trying to get by changing the boil time.
 

doogster

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I guess I am not 100% clear what you are trying to accomplish. If just trying to raise the gravity a bit, for the same volume, add some grain. Or lower the batch size, but keep the grain bill the same.

In BS, you can use the "Scale Recipe" button to change the size of your batch (or equipment profile), while keeping everything else the same (check box for "Match original gravity, color, and bitterness". Or you can click on the colored slider bar (bottom left) that says "Est. Original Gravity", and from the dialog that opens you can scale the gravity up/down, and BS will calculate the grain bill changes.
 

day_trippr

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The OP is considering shortening the boil time by reducing the pre-boil volume via recipe manipulation.
Seems simple enough, though I would expect there will be a hit on efficiency somewhere...

Cheers!
 

CascadesBrewer

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Seems simple enough, though I would expect there will be a hit on efficiency somewhere...

Yeah, most brewing software does not calculate a predicted efficiency. It just uses the efficiency value you enter (or leave at the default). If you mashed & sparged with 10 gallons of water and boiled that down for several hours, you would likely have a higher efficiency. To see the impact you would have to estimate that efficiency and change the Brewhouse Efficiency setting.

Personally, when I moved some recipes from 60 minute boils to 30 minute boils, the measured impact on my efficiency was not enough to notice so I don't change the estimate between the two boil times. In my case, I am doing full volume mash with BIAB and the mash is already pretty thin. There might be more impact for a mash and sparge process.
 
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