Brewtoad - Confused about batch size

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E_Rock

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Anyone out there use Brewtoad? I am creating a recipe but I'm a little confused about the batch size. My goal is to get 5.25 gal of wort into the primary. There is a section in equipment profile that I have set to assume .5 gal kettle loss and an evaporation rate of 1 gal/hr. So in theory, that would mean I strike with 6.75 gal of water and am left with 5.75 gal of wort post boil.

Should I set my batch size to 5.25 gal assuming the loss to kettle was already accounted for? Or should I really be shooting for 5.75 gal batch size?
 
Anyone out there use Brewtoad? I am creating a recipe but I'm a little confused about the batch size. My goal is to get 5.25 gal of wort into the primary. There is a section in equipment profile that I have set to assume .5 gal kettle loss and an evaporation rate of 1 gal/hr. So in theory, that would mean I strike with 6.75 gal of water and am left with 5.75 gal of wort post boil.

Should I set my batch size to 5.25 gal assuming the loss to kettle was already accounted for? Or should I really be shooting for 5.75 gal batch size?

You're forgetting grain absorption, chiller shrinkage, and mash tun dead space. If anything I think 6.75 gallons of water sounds a little low.

I BIAB full volume mash and I usually use 7 gallons to strike with and end up with about 5.2 gallons into my fermentor.

EDIT: After playing with the software, what you're calling "strike" is actually called boil volume. It is the amount of wort collected from the mash that will be boiled. For a 5.25 gallon batch with a 1 gallon boil off, and a .5 gallon trub loss, a 6.75 gallon boil volume is correct.
 
You're forgetting grain absorption, chiller shrinkage, and mash tun dead space. If anything I think 6.75 gallons of water sounds a little low.

I BIAB full volume mash and I usually use 7 gallons to strike with and end up with about 5.2 gallons into my fermentor.

EDIT: After playing with the software, what you're calling "strike" is actually called boil volume. It is the amount of wort collected from the mash that will be boiled. For a 5.25 gallon batch with a 1 gallon boil off, and a .5 gallon trub loss, a 6.75 gallon boil volume is correct.

Thank you! You are correct, I meant to say boil volume. Up until this point, I have been an extract brewer and for my next batch, I am going to try an all grain BIAB. I was trying to approach this in stages. Figure out what I needed to hit for boil volume and then work back for strike volume. (Is that what it's called?)

I am trying to brew a simple cream ale for the hot summer.

https://www.brewtoad.com/recipes/cream-ale-biab-5-25g

6.4 lb 6-Row
1.0 lb Flaked Corn
0.25 lb Biscuit
0.25 lb Honey Malt

1.040 OG
1.006 FG
19 IBU
3 SRM
4.5% ABV


Using http://biabcalculator.com/, for 7.9# of grain @75F with a .045 g/lb grain absorption this is what I came up with.

Total Water Needed: 7.11 Gallons
Strike Water Temp: 154 Fahrenheit
Total Mash Volume: 7.74 Gallons
PreBoil Wort: 6.75 Gallons
PostBoil Wort: 5.75 Gallons
Into Fermenter: 5.25 Gallons


Does that seem like it's in the ballpark?
 
Thank you! You are correct, I meant to say boil volume. Up until this point, I have been an extract brewer and for my next batch, I am going to try an all grain BIAB. I was trying to approach this in stages. Figure out what I needed to hit for boil volume and then work back for strike volume. (Is that what it's called?)

I am trying to brew a simple cream ale for the hot summer.

https://www.brewtoad.com/recipes/cream-ale-biab-5-25g

6.4 lb 6-Row
1.0 lb Flaked Corn
0.25 lb Biscuit
0.25 lb Honey Malt

1.040 OG
1.006 FG
19 IBU
3 SRM
4.5% ABV


Using http://biabcalculator.com/, for 7.9# of grain @75F with a .045 g/lb grain absorption this is what I came up with.

Total Water Needed: 7.11 Gallons
Strike Water Temp: 154 Fahrenheit
Total Mash Volume: 7.74 Gallons
PreBoil Wort: 6.75 Gallons
PostBoil Wort: 5.75 Gallons
Into Fermenter: 5.25 Gallons


Does that seem like it's in the ballpark?

yep that looks pretty good. Your strike water temp looks a couple degrees low. I would suggest 156-158 for a mash temp of 150-151 (you're never going to get it exact or uniform so don't stress about it).

Also keep in mind that "mash volume" refers to the volume of the container you are using to mash in, not the volume of water you would need. 7.11 gallons sounds about right to me.
 
yep that looks pretty good. Your strike water temp looks a couple degrees low. I would suggest 156-158 for a mash temp of 150-151 (you're never going to get it exact or uniform so don't stress about it).

Also keep in mind that "mash volume" refers to the volume of the container you are using to mash in, not the volume of water you would need. 7.11 gallons sounds about right to me.

Thanks so much for the feedback! I'll let you know how it turns out.
 
i love Brewtoad. it's where i do all my rough drafts and revisions of my recipes until i like them. i wish they had a setting for partigyle brewing, but nothing is perfect i guess.
 
Batch size is what you want in the fermenter.

Calculated Boil Size = Batch Size + Trub/Chiller Loss + Evaporation Rate * Boil Time.

If you're calculated boil size is more than your Kettle Volume it'll calculate top-up water.
 
Batch size is what you want in the fermenter.

Calculated Boil Size = Batch Size + Trub/Chiller Loss + Evaporation Rate * Boil Time.

If you're calculated boil size is more than your Kettle Volume it'll calculate top-up water.

I don't know if this is a bug with the website, but for my recipes the trub/chiller loss variable never saves with the recipe. The recipe calculates OG based on batch size, so you're better off setting the batch size to the amount of wort you have at the end of boil because it will properly reflect the OG.
 
Does anybody know why brewtoad calculates "maximum safe kettle volume" higher than "kettle volume"? It does not give me any sense. I absolutely do not have clue how to set this properly. Look at the attached picture. Is this ok? How can I have maximum safe volume higher than total volume of my kettle?

Selection_676.png
 
Looks like (batch size + boil off) x 120%

It's telling you that boiling 29L in a 30L pot is a bad idea.
 
Looks like (batch size + boil off) x 120%

It's telling you that boiling 29L in a 30L pot is a bad idea.

Yes, I know boiling 29L in 30L pot is a bad idea, but the brewtoad should be so inteligent it will tell you something like "maximum safe amount for your 30L kettle is ~24L, so you will have to top up 5 liters of water when racking into fermenter."
But instead of that it will tell you you can safely boil 35.75L in a 30L kettle :)
 
OK, so I understood now the "Maximum safe kettle volume" means "your desired batch size" + "trub/chiller loss" + "evaporation" +"some magic constant". It totally ignores the volume of kettle. Really confusing. Never mind...

Now I even discovered a bug in brewtoad. If you use US Customary units, all is fine. But if you want, as I want, to use Metric units, it does not calculate the volumes properly. If you have smaller kettle than the batch size, brewtoad should use partial boil type and it should calculate the amount of top up water. It also does, when you use US Customary units. But if you change your profile to prefer Metric system and change this as well in the equipment, it will still use the full boil type.

See the same recipe when using both units in the attachment.

Selection_945.png


Selection_946.png
 
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