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the_city_of_homebrew

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Hi all

My understanding is that with BIAB method you do not need to sparge. With this in mind how much water should I mash with initially?

I have 4.8kg grain bill and a 32L pot, any help?
 
If you're not sparging/rinsing then do a full volume mash. You might have to drain a little first wort and add it back to the boil.
 
If you're making 23 litres, you need 23 plus grain absorption and evaporation losses. And any losses to hops and trub. Grain will soak up about 4 litres, and you want to start the boil with about 27, so 31-32 litres seems about right. So you won't fit it all in. Use as much as you can, and top up the kettle after removing the grains. If you can rinse the extra water through the grains, all the better.
 
This is useful as I hadn't worked out the volumes for my biab plans. I've got a 30L pot and want to do 10L batches mostly. So about 16L sounds about right for a full volume mash. My main concern is heat lass as with grain and water I reckon the oot will still have about a third clear headspace above the mash, expand even with a duvet on the oot I suspect it will lose a fair bit of heat. Need to experiment. If I lose too much heat I'll get a mash tun. Any excuse for more kit...
 
For full true BIAB where you put the full volume of liquid you need into the pot to begin with I think most go for a 40 litre pot..

Many people will use smaller and just do a sparge and top up their pot before the boil.
 
Fantastic thanks for that. In after 21L. Found a calculator online that states 28.49L full volume with the view that this will create 26.69L preboil wort. This sound about right?
 
the_city_of_homebrew said:
Fantastic thanks for that. In after 21L. Found a calculator online that states 28.49L full volume with the view that this will create 26.69L preboil wort. This sound about right?
Click to expand...
the pre boil sounds about right what you have to remember is you're going to lose about 4-5 liters to grain absorbtion in the mash.

Add that to your pre boil volume and you're about 31 liters of water. That and 4.8 KG of grain will not fit into a 32liter pot..

What you can do instead which is what some of us do and what I planned to do last night before my boiler just didn't play ball is.. mash in 15 -20 liters say and then sparge in about 15 liters of water dunk sparging in say your FV.. add that water back to your mash water as it comes up to the boil and you're away.
 
Looked at a few BIAB videos online. Some people look to wrap up their pot in blankets etc to keep the pot at the right temperature. Just wondered can anyone advise, is this really necessary? Would it make a massive difference if you just stuck the lid on and nothing else?

Also, when it comes to boiling the wort, some people make reference to a "rolling boil". I take it that once it is at that stage you can just turn down the heat and simmer for an hour or so?

Did try a BIAB a while back but the OG was pretty poor compared to what I was expecting..........the resultant beer was a bit meh.
 
Does anyone use a Sous Vide with BIAB. This will keep a constant temperature and flow. I used mine for steeping grains and it worked out well.
 
thesteve said:
Looked at a few BIAB videos online. Some people look to wrap up their pot in blankets etc to keep the pot at the right temperature. Just wondered can anyone advise, is this really necessary? Would it make a massive difference if you just stuck the lid on and nothing else?

Also, when it comes to boiling the wort, some people make reference to a "rolling boil". I take it that once it is at that stage you can just turn down the heat and simmer for an hour or so?

Did try a BIAB a while back but the OG was pretty poor compared to what I was expecting..........the resultant beer was a bit meh.
Click to expand...


You'll lose a lot of temp if you don't wrap/insulate your vessel. I tend to just use a few towels and I lose about 1°c in an hour. If you stir a few times during the hour then you should see your mash efficiency improve significantly.
 
thesteve said:
Looked at a few BIAB videos online. Some people look to wrap up their pot in blankets etc to keep the pot at the right temperature. Just wondered can anyone advise, is this really necessary? Would it make a massive difference if you just stuck the lid on and nothing else?
Click to expand...
I'm BIABing in a 30L electric boiler that has no insulation. If I don't wrap it up during the mash it'll lose about 3C by halfway through so I have to switch it on for a few minutes to get it back up. So these days I wrap it in a blanket and that keeps the temperature pretty steady for the whole mash.
 
I do. 2.5 gal biabs in a 33 l pot. No probs. 16.5l is about standard. I use beer Smith to calculate.

You do loose a little heat over the hour put I just turn the gas on, making sure the bag isn't touching the bottom of the pan. My bag is too short, but when I used a smaller pan I used an upturned silicone steamer to stop anything touching.

I give it a stir every now and again to distribute temps and improve efficiency. Easy peasy. Never noticed anything wrong with my beer.
 
thesteve said:
Looked at a few BIAB videos online. Some people look to wrap up their pot in blankets etc to keep the pot at the right temperature. Just wondered can anyone advise, is this really necessary? Would it make a massive difference if you just stuck the lid on and nothing else?
Click to expand...
Well.... you won't die. I don't have a proper mash tun and have done loads of wrap in a duvet, put the pot in the oven, insulate with 70 metres of bubble wrap, etc - and I always got lots of temperature drops, and of course that has an outcome on fermentability.

Initially I used to sweat it and I really don't any more. I've said a few times on here that no matter my ingredients I always end up with a 5.2% beer, and that's not a joke and it happened about 7 times in a row and it was just because of my mash being so insouciant.

At the end of the day the beer was fine to lovely. Go to http://brulosophy.com/projects/exbeeriments/ and put mash temperature into the search and there's definite differences but perception differences aren't siginificant.

Upshot? You can mess things up and get away with it.
 
If you do a smaller batch you'll have more room.

No particular reason why you MUST make 21-24 liter batches.

I do 9 to 13 liter batches and am quite happy with a 20 liter pot.

All the Best,
D. White
 
I don't have a full sized boiler - 25l - and just accept I'll be getting 15l in to my fv each time. No great loss. If I really want a full 5 gallon then I just up the grain bill and back liquor to the required OG.
As for heat loss, I always aim for a starting temp of 66c after the grain is added, so strike temp of about 69c for my usual volumes. I put a blanket on the lid only and that alone made the temp drop reduce from 4c over an hour to 2c.
Losing 2c over 60 minutes is not going to make the slightest bit of difference in the grand scheme of things.
 
Yeah same with everyone else.. aim for 69ºc dough in nice and slow and thorough especially with BIAB.. lid on I use an old winter coat around my pot with a thick blanket on.. I usually stir half way through and at the end.. It may end up at 65 or 64ºc at the end if I do not add any heat and just carry on from there
 
Loosely, I'll work to 3 litres / kg but don't get too hung up on it. I have a 32L pot & work to 18L output. That's partly due to the quantities my LHBS sells grain in & gives me ~5% abv. I do use a jug sparge to rinse out some of the trapped sugars. It takes a bit of time but works for me.
 

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