BIAB- Mash / Sparge Question

Lets say I am mashing in at 150f for 60 minutes. In another pot I have 170f of water-

After the 60 minutes- my idea would be to pull grain bag out, let drain a bit- press- push- get as much out as possible- Then letting the bag go back into the pot- and adding the 170f mash out water-(( yes will be higher temp- because of the drop from adding it into mix..)) for the final 10 minute - tea bag / mix / paddle -


do you lose efficiency this way because your still mixing all that new water into the same pot with the original mashed wort?

Would it be better to dual pot ( like I did the first time ) (mash in one, mash out/sparge in other ) separately? I didnt find that to be too hard- but im wondering if I can effectively do it on one pot- and will I gain anything or lose.

Looking at getting the most from the grains as possible- yet not adding any off flavors etc.

I wouldn't press and squeeze the bag. But rather after draining it as much as you can, proceed to dip it several times in the 170-ish water in the separate kettle. Then let it drain over a large bowl on the side, and pour those runnings back into the main kettle. Instead of placing the bag in the bowl, I hang tie it and let gravity do the work for me.

I utilize dual kettles when I brew BIAB w/partial mash indoors (as well as the above technique). It works great and I usually reach 75-80% efficiency no problem. Some people get even higher than this via the same method.

are you able to do full volume BIAB or do you not have a large enough kettle? If you do, just use the no sparge method. If you can't I would do a dual vessel system with a batch sparge.

What I do (whether it is rightor wrong) is after draining the bag as much as I can. I put it into a strainer and then slowly poor my sparge water over the grain bag. Always got good results from that.

If you have a big enough pot to do the full volume of water right from the start, then you can mashout with the grain bag still in the pot. After the 60 min. mash, just heat up to 170, stirring the crap out of the grain to normalize the temp, and let it sit at 170 for 10 minutes, still stirring the crap out of the pot.

The science is that the 170 degree water activates different enzymes in the grain that will separate some of the more complex sugars from the grain and leave them in your wort. More conversion = higher efficiency.

If you can't fit the full volume into one pot, then you want to do as everyone else is suggesting and dunk sparge by dipping the grain bag into your 170F sparge water in the other pot. This is just as good and efficient, so even if you have a big pot, stick with this method if you are more comfortable with it.

Good luck!

TopherM said:

If you have a big enough pot to do the full volume of water right from the start, then you can mashout with the grain bag still in the pot. After the 60 min. mash, just heat up to 170, stirring the crap out of the grain to normalize the temp, and let it sit at 170 for 10 minutes, still stirring the crap out of the pot.

The science is that the 170 degree water activates different enzymes in the grain that will separate some of the more complex sugars from the grain and leave them in your wort. More conversion = higher efficiency.

If you can't fit the full volume into one pot, then you want to do as everyone else is suggesting and dunk sparge by dipping the grain bag into your 170F sparge water in the other pot. This is just as good and efficient, so even if you have a big pot, stick with this method if you are more comfortable with it.

Good luck!

Click to expand...

Trying to figure this BIAB process out.

Can I mash out with the grains minus an amount and do a sparge up to the volume? Say I have 5.5 gallons in the pot/kettle with the grains that I mashed, raise that to 170*, hold for 10 minutes, then pull grains back out and rinse the grains with about 1.25 gallons of 170* water to get my preboil volume of 6.75 gallons?

Don' forget about water loss in the grain, as it can be significant based on grain bill size and how much you squeeze out. You need to either mash with more water, or sparge with a higher amount to make up for the loss.

Tropher has the processes down. Don't worry about mash thickness with BIAB. It's not going to change attenuation much if any at all. You will also get high efficiency mashing thin. The science is a little off, but close. The alpha enzymes go into overdrive as the temperature climbs through 160, but 170 is for denaturing the enzymes.

For a full-volume BIAB, you start with:

Batch Size (i.e., 5.0/5.5 gallons, or whatever)

+

Loss to grain absorbtion (This is only about 0.3 gallons in my process, but I squeeze the daylights out of the bag)

+

Loss to boiloff (this is about 1.2 gallons/hr. on my pot, but all pots are different. Boiloff is a function of surface area)

+

Loss to trub (however much hotbreak you leave behind post boil AND however much you leave behind when you rack from primary...on my system this # is about 0.5 gallons total)

+

Loss to contraction (you lose somewhere about 0.2-0.3 gallons during cooldown just due to the hot liquid contracting as it cools)

=

Starting water volume.

For a typical 10lb grain bill on a 5.25 gallon batch, I start with between 6.8-7.2 gallons of water.

If you were going to split it up into two pots, you would still use that same amount of water, you'd just mash in at least 1.25 qts/lb grain in the main pot and dunk sparge in the rest of the water. If your pot is big enough, through, just do everything, including the mashout, in the single pot.

Make sense?

BTW, BeerSmith will calculate all of this for you. It's $22.00 from Birdman Brewing (the cheapest I've found). It is insanely feature packed, and I'd honestly happily pay $100-150 for everything it simplifies for my brewday.

Good luck!