Brew in a Bag Efficiency

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davidgrace

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I understand that efficiency can be increased when brewing in a bag by adding extra grain. Does it also work by adding less water to end up with slightly less beer?
 
The best ways I've found to increase efficiency in a staggering 115 BIABs are these. Mash with 6l of water less than you'd need for a full volume (for a 23l brew), drain, open the bag and add 6l of warmer water and leave for 10 minutes, stirring occasionally. Drain again and add to the bulk which you are currently heating.
Overnight mash. Get it going in the evening before you brew. Tuck it up overnight and brew the next day. You should up your strike temperature to get a higher initial mash temp. This helps to avoid an overly dry beer.
Do these 2 things and you might up your efficiency by 15%.
I used 4 kg of MO and 350g of crushed crystal in my last brew and got 23.25l in the FV @ OG 1.050. That's about typical for me.
 
If you mill a good fine crush and mash in the full volume stir well and dough in and stir 30 mins and well at the end you can get 70%+ however if you wish add an extra hundred grams of grain is no great shakes
 
A fine grind, if you grind your own is a great help. I mash in about 4 gallons for a five gallon brew, then sparge by dunking the bag in an FV with another gallon or so and give it a stir.
I've no idea what my efficiency is but it's quite a lot higher than Greg Hughes recipes expect, to the extent where I've had to cut the pale malt quantities quite a bit to get down to the stated OG.

I also mash at quite a low temperature - 146F (63C) or thereabouts.
 
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They don't increase efficiency just make up for lack of it but yes both will do the same.
Thanks for the correction. Of course, adding more grain or less water makes up for lack of efficiency. I am thinking of 1 litre less water for an 11 litre brew. Would you advise 1 litre less?
 
The best ways I've found to increase efficiency in a staggering 115 BIABs are these. Mash with 6l of water less than you'd need for a full volume (for a 23l brew), drain, open the bag and add 6l of warmer water and leave for 10 minutes, stirring occasionally. Drain again and add to the bulk which you are currently heating.
Overnight mash. Get it going in the evening before you brew. Tuck it up overnight and brew the next day. You should up your strike temperature to get a higher initial mash temp. This helps to avoid an overly dry beer.
Do these 2 things and you might up your efficiency by 15%.
I used 4 kg of MO and 350g of crushed crystal in my last brew and got 23.25l in the FV @ OG 1.050. That's about typical for me.
Overnight mash. Do you mean mashing for an hour and then leaving the wort in the pot overnight? If so, is the bag still in the pot overnight? At what temperature would you leave it? Would it mean simply bringing the wort to the boil next day for an hour and adding hops at set times?
 
By far the simplest ways to improve your efficiency when you BIAB have to be:-

Stir properly when you dough in, then every 20 minutes.
Get your mash pH right.
Mash for a full 90 minutes, not just 60.
Mash out, and consider a sparge step.

You can get over 80% easily with these steps, add in a recirculation pump setup and you can easily get over 90% into the FV.
 
Sounds like good advice that I may have to steal,

Im currently getting 50% efficiency and I recirculate. my next brew will deff use your tips
 
Overnight mash. Do you mean mashing for an hour and then leaving the wort in the pot overnight? If so, is the bag still in the pot overnight? At what temperature would you leave it? Would it mean simply bringing the wort to the boil next day for an hour and adding hops at set times?
I tend to use a strike temp. of 70C, add the Maris Otter and, as has been said, stir well. Tuck it up in a quilt and as much insulation as you have. I use a motorcycle jacket. If you have an insulated vessel all the better. Yes, I would leave the bag in but my own method is a heavily modified BIAB. There's no bag involved at this stage! Then just leave it 'til the morning. I end up with a temp. in the mid 50s celcius. I then raise the temp. to 76C to steep my crystal. This is just to give the crystal time to impart its flavour. I then drain/ sparge/ drain and heat to a boil. I then add the bittering hops etc. I use a bag as a filter when I drain for the grain and hops stages but not in between times. I just prefer this way.
 
Overnight mash. Do you mean mashing for an hour and then leaving the wort in the pot overnight? If so, is the bag still in the pot overnight? At what temperature would you leave it? Would it mean simply bringing the wort to the boil next day for an hour and adding hops at set times?
I tend to use a strike temp. of 70C, add the Maris Otter and, as has been said, stir well. Tuck it up in a quilt and as much insulation as you have. I use a motorcycle jacket. If you have an insulated vessel all the better. Yes, I would leave the bag in but my own method is a heavily modified BIAB. There's no bag involved at this stage! Then just leave it 'til the morning. I end up with a temp. in the mid 50s celcius. I then raise the temp. to 76C to steep my crystal. This is just to give the crystal time to impart its flavour. I then drain/ sparge/ drain and heat to a boil. I then add the bittering hops etc. I use a bag as a filter when I drain for the grain and hops stages but not in between times. I just prefer this way.
 
The other considerations when it comes to efficiency is your liquid losses along the way. Any wort that doesn't make it into the fermentor is going to hit your efficiency. BIAB has the advantage of not losing anything going between mash tun and kettle but if you have lots of dead space in your kettle or you use lots of absorbant leaf hops you will lose some efficiency points. You can help by squeezing the bag when you drain it. Squeezing leaf hops to get out some wort and tilt your kettle to get as much wort into the fermentor as possible. This does mean that you transfer a bit more trub but I'd prefer to let it ferment out and pack down nicely at the end of fermentation rather than leave loosely packed kettle trub.
 

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