Cooking a double batch

[panspermian]

Hi guys,
I got a 30L mash tun and 30L kettle.
I recently purchased a 70L stainless fermenter.

So my question is,
To make 60L or so, would it be best to mash all the grain at once and then just top off the extra 30L with boiled water or cook the recipe twice?
I was thinking there might be a limit to how much grain can be mashed with so much water.
Would too much grain be less effective?

 

[panspermian]

I just found a very similar thread

 

[Danscraftbeer]

Always takes a certain amount of water to extract the sugars from the grain mass. Bigger grain mass = more water, more boiling down to reduce. Its a given if you care about efficiency targets.
In laymans homebrewing terms if you want to get a bigger gravity in a smaller capacity concentrating the grains it will fall short in efficiency defeating the goal.
Larger pre boil volumes + Longer boils to reduce volume gets good efficiency. Or throw in loads more grains getting lower efficiency.

 

[Danscraftbeer]

I do Batch Sparge and partial boilings. Take the first run off and get it boiling. Sparge, ad the second running and re boil. Add the following running's and reboil etc. Its the way to max your brewing capacity, avoid boilovers and get some good efficiency of the grain.

 

[panspermian]

So,
I only have 2 vessels so mash all the grain.
Boil etc.
Transfer to fermenter,
Heat sparge water in kettle, run back over grains in mash tun, back to kettle and boil etc.....

 

[malt junkie]

I'd run a standard batch twice, a day or so apart. Pitch yeast on the first batch and just as it's getting into full swing add the second batch (known as double dropping).

Upsides

1. makes proper use of available equipment (you'll get decent efficiency)
2. Your yeast will have time acclimatised to conditions and more than double in population by the time you add the second half of wort
   
3. you get to brew twice!!
   
4. You will use parameters you are used to and will therefore be able to follow a brewing practice you are familiar with, and be able to continue to improve this process.

 

[Danscraftbeer]

So,
I only have 2 vessels so mash all the grain.
Boil etc.
Transfer to fermenter,
Heat sparge water in kettle, run back over grains in mash tun, back to kettle and boil etc.....

Do all the mash run offs while boiling each run off adding sparge run offs until you get to maximum kettle volume. This takes time but are you into it?
Then start your pre boil time from there. I go 90 minute boils from maximum kettle volume.
Hops etc. Finish boil. Chill.
Then to the fermenter.

 

[manticle]

Get a bigger kettle. 30L is tiny - you'll get 25L max preboil without boilovers unless you're boiling with a candle.

 

[S.E]

Hi guys,
I got a 30L mash tun and 30L kettle.
I recently purchased a 70L stainless fermenter.

So my question is,
To make 60L or so, would it be best to mash all the grain at once and then just top off the extra 30L with boiled water or cook the recipe twice?
I was thinking there might be a limit to how much grain can be mashed with so much water.
Would too much grain be less effective?

How long between brewing batches? Better to brew your recipe twice if you have time? If you can chill the first batch and pitch yeast while brewing the second, then chill and add that to the fermenter?

 

[S.E]

I'd run a standard batch twice, a day or so apart. Pitch yeast on the first batch and just as it's getting into full swing add the second batch (known as double dropping).

Upsides

1. makes proper use of available equipment (you'll get decent efficiency)
2. Your yeast will have time acclimatised to conditions and more than double in population by the time you add the second half of wort
   
3. you get to brew twice!!
   
4. You will use parameters you are used to and will therefore be able to follow a brewing practice you are familiar with, and be able to continue to improve this process.

We are sort of thinking alike but double dropping is not two separate batches,it is a single batch aerated twice.

 

[panspermian]

Yeah I'm starting think just cook two batches.
It's one of those fancy pants SS brew tech fermenters with built in immersion chiller.
Today I bought a cheap $30 100L plastic storage bin from bunnings. Use this as my immersion chilling water thing.
Install ball valve tap down the bottom, pump, return hose will just be siliconed through a hole in the lid.

 

[Danscraftbeer]

Got any pics, or links on that?

 

[panspermian]

What in particular?

 

[S.E]

Yep , bit confused here also?

 

[manticle]

We are sort of thinking alike but double dropping is not two separate batches,it is a single batch aerated twice.

Draflaussen is the term he meant I think.

 

[Lionman]

What OG are you aiming for at 60L? 1.050?

With such a tiny kettle and mash tun, you will likely need to do 3 consecutive batches. I have a 40L single vessel and its pushing it to do much more than 7KG.

Mash 5KG into 25L, runoff, sparge, boil.
While that one is boiling mash another batch
etc.

It will take around 15kg of grist to get to 1.050 OG in 60L.

Another option is to do reiterative mashing. it will decrease the time/energy used but reduce your efficiency and hop utilisation. You can do 3 mashes but just 1 boil, cutting out 2+ hours of boiling and the energy used to do so.

Mash 5KG, sparge, Mash another 5KG into the wort of the first mash, sparge and so on.

After three mashes you should reach a gravity of around 1.160.

Boil and bitter to around 100 IBU.

Dilute the 20L of wort in the fermenter to 60L total and you should end up at around 1.050 OG and mid 30 IBUs for a APA.

I havent tried this but it should work. I have been planning to do this but split a boil a cross 2 cubes and dilute with boiled water.