OG Formula Option in Brewer's Friend

[jeeppilot]

I use the BIAB method and have my equipment profile set. There is a new(?) option I just noticed that I'm confused with. Under "Advanced Recipe Options and Stats", "Equipment Profile", it says, "Use the following option from your equipment profile to change the original gravity formula using boil size instead of batch size." The option the states Use boil size and boil evaporation rate: 1.25 gallons/hour

With my current recipe, selecting this option drops my OG by 12 points. My "Batch Size" is set to 2.5 gal (fermenter) and "Est Boil Size" is 4.8 gal. Can anyone give me a better explanation of this so I can make the correct selection? Thanks!

 

[pricelessbrewing]

My recommendation is to not use it. Not sure what the intended use for it is, but I don't think it's working correctly.

 

[ScrewyBrewer]

When you switch to ‘equipment profile’ you’re essentially looking at brewhouse efficiency. Which includes sugars lost in hoses, pumps and other dead space.

ezRecipe Design lets you choose between ‘Kettle’ and ‘Fermentor’ modes. I select ‘Kettle’ if sharing recipes with friends. I use ‘Fermentor’ when setting up or making changes to my brewing system.

 

[jeeppilot]

When you switch to ‘equipment profile’ you’re essentially looking at brewhouse efficiency. Which includes sugars lost in hoses, pumps and other dead space.

ezRecipe Design lets you choose between ‘Kettle’ and ‘Fermentor’ modes. I select ‘Kettle’ if sharing recipes with friends. I use ‘Fermentor’ when setting up or making changes to my brewing system.

Brewers Friend has Kettle and Fermenter modes too. I use this the same way as you. I’ll have to play around with some of my other recipes to see if the difference between the modes in question creates the same difference. The current recipe has a 90 minute boil and high OG, which I suppose could lead to even greater differences depending on its intent. I’ll report back.

 

[pricelessbrewing]

Here's my thread on this setting, from what I can tell it's not accounting for kettle losses properly.

https://www.brewersfriend.com/forum...er-volumes-and-use-equipment-boil-size.11715/

 

[jeeppilot]

Here's my thread on this setting, from what I can tell it's not accounting for kettle losses properly.

https://www.brewersfriend.com/forum...er-volumes-and-use-equipment-boil-size.11715/

Still trying to make some sense of this... and I think your linked post definitely hit one part correct. Kettle losses and misc losses and not factored here, but I don't think they need to be. Wort left behind is an efficiency function, not an OG factor.

Anyway, I looked at 3 recipes of mine and the differences between the numbers with this "boil size and evaporation rate" box selected. For reference, my boil off rate is 5 qt/hr or 1.25 gal/hr and my batch size is set to "fermenter". Some points I found:

- PRE-BOIL gravity changes when this box is selected. For both 60 min and 90 min boil recipes, the pre-boil gravity drops an average of .05 when selecting the box. Obviously, this impacts the OG down the line.

- Water requirements do not change based on the selection of this box alone.

- Selecting Batch Size Target to "Kettle" disables the selection of the Boil Size and Evaporation Rate box and changes the water requirements with all others remaining the same.

So, the big question for me is, since my grist bill doesn't change and the water requirements don't change, why would the pre-boil gravity change? What am I missing?

(Also posted to your linked thread on BF)

 

[ScrewyBrewer]

@jeeppilot this is how I interpret those options, although I don't know how they work in BF.

Kettle: Calculates the percentage of sugars converted in the mash that remain in the wort at the end of boil (aka: Lauter Efficiency). Select 'Kettle' when sharing recipes with friends since their brewing setup most likely isn't the same as yours.

Fermentor: Calculates the percentage of sugars converted in the mash that remain in the wort when it goes into the fermentor (aka: Brewhouse Efficiency). Select 'Fermentor' when sharing recipes to be brewed on other systems.