Make 30L by BIAB in 35L pot - can it be done?

[ballantynedewolf]

My mate and I have been BIABing with his 35L pot and getting on quite well. I have a crap-load of fermenters and a temp-controlled cupboard that can hold 2 ferms at a time, so the 18L length constraint most software places on this 35L pot has been chapping my thighs a bit. There's a few hours work here and only 18L to show for it.
So I've been scheming to try and push the length to 30L using adjunct sugar (I love Belgian so this is fine) and cooking my bittering hops separately in a pressure cooker so that I can boil less. I'm making a pale-coloured ale, so boil darkening is of no interest to me. So here is my first draft procedure and I'd be interested in your thoughts...


Method for making 30L 1.055OG Belgian specialty ale by BIAB using a 35L kettle

1. Add 30L water and heat to protein rest strike temp (c53C)(up to 50% of my base is burghul wheat)
   
   
2. Add 6kg of base, 1kg of specialty (toasted, crystal and oats)
   
   
3. Rest at 50C for 20mins
   
   
4. Heat to 67C AFAP
   
   
5. Mash @ 67C 60mins
   
   
6. Pull bag, squeeze, top up to 30L (maybe sparge squeezed bag with a 2L kettle of 70C water)
   
   
7. Boil 30mins while cooking bittering hops for 10 @ 130C
   
   
8. Add hop tea, table sugar and chiller coil at 10mins to go
   
   
9. Flame out and add flavour hops and steep for 10min
   
   
10. Top up to 34L w chilled water (allowing for 1L cooling loss)
    
    
11. Immersion chill to 18C
    
    
12. Fill 2 fermenters to 15L (3L trub loss)
    
    
13. Use two 1L starters to get length up to 30L (1L each fermenter loss)

 

[RdeVjun]

Maybe. I don't have my records in front of me but I did something vaguely similar once.

I'd sparge in as much water as you can, use the plain water at 6 for it as adding plain water at that stage is such a waste- you should be using it to improve the efficiency. Basically you want the kettle full to the brim/ as far as you dare at boil start, add sparge to offset evaporation losses and pick up a few more gravity points.

You've researched Maxi-BIAB perhaps?

 

[ballantynedewolf]

Maybe. I don't have my records in front of me but I did something vaguely similar once.

I'd sparge in as much water as you can, use the plain water at 6 for it as adding plain water at that stage is such a waste- you should be using it to improve the efficiency. Basically you want the kettle full to the brim/ as far as you dare at boil start, add sparge to offset evaporation losses and pick up a few more gravity points.

You've researched Maxi-BIAB perhaps?

Deadset that's the best post I've ever read on a homebrew forum: modest, helpful and with a link to a whole new world of awesomeness. I'd never heard of MaxiBIAB but I had pondered what L:G ratio limit I could push - 4kg/L it seems.
I've been pondering attempting a Tim Taylors Landlord clone. With it's OG of 1.042 and sucrose secondary I reckon I could make two full fermenters using maxiBIAB. All I'd need is a strong grain bag and some way to swing its weight.
Thanks RDeVjun

 

[mtb]

Some malts are prone to DMS if not boiled for a while ie 60-90min, namely pilsener malts. I'm not an expert on the subject but more reputable members discussed it here - https://aussiehomebrewer.com/threads/diacetyl-and-dms-from-short-boils.94701/

 

[RdeVjun]

You're welcome OP, no problem, all part of AHB's fabulous service.

4L/kg I think you mean though? With MaxiBIAB, that's 5kg in 19L, it works with ease, can easily go stronger but with this method the efficiency suffers considerably as a result of the fixed mash volume.

I'll consult my records at home, let you know what I did, was for the Belgian Imperial Chocolate Stout collaboration of SEQld case swap fame IIRC. I don't remember being overawed by superb efficiency though, but it came close to expectations.

Oh, also bear in mind that hops utilisation may suffer at higher boil gravity, but that is not insurmountable.

TTL is a personal favourite, modelled mine on the good Doctor's (Smurto) recipe, while a pound of sugar in it is routine for me, no hesitation in suggesting that for your experiment.

Good luck!

 

[Lord Raja Goomba I]

Another option is an adaptation of my two pot stovetop method, whereby you mash in the esky, thus creating the headspace needed to make 30-odd Litres (because the headspace is no longer taken up by grain). Bucket in bucket lauter and then run into the pot. It's pretty ghetto but it does work.

 

[ballantynedewolf]

You're welcome OP, no problem, all part of AHB's fabulous service.

4L/kg I think you mean though? With MaxiBIAB, that's 5kg in 19L, it works with ease, can easily go stronger but with this method the efficiency suffers considerably as a result of the fixed mash volume.

I'll consult my records at home, let you know what I did, was for the Belgian Imperial Chocolate Stout collaboration of SEQld case swap fame IIRC. I don't remember being overawed by superb efficiency though, but it came close to expectations.

Oh, also bear in mind that hops utilisation may suffer at higher boil gravity, but that is not insurmountable.

TTL is a personal favourite, modelled mine on the good Doctor's (Smurto) recipe, while a pound of sugar in it is routine for me, no hesitation in suggesting that for your experiment.

Good luck!

Ah yes, sorry I did mean 4L/kg.
I'm aware of the lower hop utilisation at high gravity, so I have been experimenting with cooking my bittering hops separately in a pressure cooker. This saves a lot of gas because it's all over in 10 mins, and so I had thought of shortening my boil, but as LRG points out, my pilsener malt in my Belgian ales may be a bit DMSy. As the MaxiBIAB method is unconstrained by evap loss, it may be wise to play safe and just go back to using more hops instead. They do go off on the shelf after all.