Partial BIAB - noob question warning

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Yuz

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Hey Brewers, seems it's time for NY resolutions, well mine is to up the game and get into grains. Well, almost :)

Firstly - my apologies if this has been covered before but I'm hoping on some feedback specific on my equipment and process. This is for a typical 23L batch (maybe 21L?).

Gear first:
1) 12L Alu Stockpot that has served me well so far
2) Waeco 13L Esky:
- No modifications / taps / ball valves; It's brand new and I want to use it as an ice box as well occasionally
- I think Polypropylene and the foam gasket should handle 75deg no prob?
- BIAB bag to suit

Process:
1) Place the bag in the Esky and mill grain directly into it - say, total of 3kg of Base and a bit of Crystal
2) Fill 9L of 75deg water and let is sit for an hour
3) Remove the bag full of grain and chuck it into empty Stockpot
4) Sparge with 80deg water - approx 2L with the bag in a strainer
5) Pour the wort from Esky out directly into the pot. This should give 11L of pre-boil volume and prob 10L final (lid closed so there's not much evaporation loss)
6) Bring to boil, hop schedule and boil for 45min to an hour
7) Add 1.5kg DME and cool down in the sink (same as I've been doing with extract brews)
8) Mix with pre-chilled water in fermenter to make to total batch volume

Any potential issues with this setup or recommendations?
Thanks for your help!
 
Super-interested in this thread as this is my next step as well.

Regards your volumes, shouldn't you assume that a certain amount of water will be soaked up by the grain, meaning that you will end up with less than 11lt?

I have found another forum with a great page on partial mash - process with pics - can link you to it if you are interested. Better to PM me as I'm not sure how folk around here take it if you link to other/competitor forums.
 
Regards your volumes, shouldn't you assume that a certain amount of water will be soaked up by the grain, meaning that you will end up with less than 11lt?

I have found another forum with a great page on partial mash - process with pics - can link you to it if you are interested. Better to PM me as I'm not sure how folk around here take it if you link to other/competitor forums.

Well, considering I only have a 12L stockpot, a bit less than 11L of pre-boil volume would be welcomed as it will need some head space.

Yeah, sure - flick me the details as I've been researching this method for a while but want to keep it simple as, and get the basics right, with the gear I already have...

Cheers!
 
Your looking at about a litre per kg of grain for absorption.
Also don't leave the lid on while boiling to prevent DMS.
 
Super-interested in this thread as this is my next step as well.

Regards your volumes, shouldn't you assume that a certain amount of water will be soaked up by the grain, meaning that you will end up with less than 11lt?

I have found another forum with a great page on partial mash - process with pics - can link you to it if you are interested. Better to PM me as I'm not sure how folk around here take it if you link to other/competitor forums.
If the link is relevant to the topic, it is absolutely fine
 
As above - you’ll lose 1- 1.1 L to absorption but can make the extra up with your sparge if needed.

Only thing I would add is exercising caution pouring hot wort. There’s a reason most brewers use taps and hoses.

Otherwise, looks good. Have at it.
 
Yeah good call. I gave my hands a very nasty scald once which required medical attention.

Also oxidising hot wort by splashing it around is not ideal.

You should be able to install a discrete tap maybe in the drain hole
 
Thanks for the replies gents. Re safety - I'll be handling a 10kg object, moved from a bench top and poured to the pot below, so it should be manageable and I have long gloves just in case and will dress appropriately. But yeah, a tap could be on the cards if this setup works.

Looking further into this I tweaked this recipe attempt / process as per your recommendations, which should give OG of about 1.040?
Here's Revision B of Partial BIAB'ed Pils-type:
  • Heat up water to 70C and fill up 12L into Esky (Final volume approx 9L of mashed Wort due to absorption)
  • Place 3kg Base Malt (Pilsner) & 0.25kg Speciality (CaraHell) in the bag and into the esky and mash evenly; Close the lid and mash for an hour;
  • Fill 2L in the Pot @ 80C and Transfer bag to the pot (dunk sparge); leave for 10min and strain
  • Take bag out and fill Wort from Esky into the Pot
  • Total pre-boil volume approx 11L
  • Add 1kg Light DME and bring to simmer
  • Hop schedule and simmer for an hour (Lid off the Pot)
  • End boil volume 9.5L (? I'm guessing)
  • Mix with chilled water to 21L and aerate
PS - Matty, what's DMS?
PPS - I understand the gear is on a very small scale but that's all I got for the time being for this experiment...
 
Update - just stumbled across Ian's BIAB calculator! Awesome :))))

SeeFar - buttery popcorn, honey and creamed corn flavours sound like they could make some yummy vape juice variations!
 
This is similar to what I do however I make 12L batches and use a 5L stock pot so scaled up would be about the same as you.
Works great, the only issue I found to start with was working out what temp I needed the water to get the right mash temp in the esky.
 
This is similar to what I do however I make 12L batches and use a 5L stock pot so scaled up would be about the same as you.
Works great, the only issue I found to start with was working out what temp I needed the water to get the right mash temp in the esky.
Yeah, a bit of guess work and trial and error. Largely depends on the total volume, grain and ambient temps I guess - so I have a boiled kettle and a bottle of room temp water on stand by. But, as with anything - live and learn :)
I remember by very first batch - weighing up DME and hops down one +/- one gram lmao :rolleyes:
 
The process sounds good and should work, but...
I'd recommend more head space in the stock pot than 1L. Once you hit the boil there'll be heaps of foam and will likely boil over onto your stove.
One alternative to consider, if you can, is moving it outside onto a gas burner. Boil over? no problems.
 

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