Originally Posted by cockybitz
Not mentioned is that the enzymes are in the liquid, not so much the solid of the mash. When decocting it is important to pull a generous amount of grain while leaving the liquor-- and thus the enzymes- behnd.
Right! And when the decoction is returned to the tun, all the enzymes left in there can go continue to work. The enzymes denatured during the decoction is kept minimal, since most were left behind in the first place. That's why balanced grainbills are important, to make sure there's enough buffering power left in the bulk of a mash.
What I was referring to however is while I'm batch sparging my first beer, I run off and sparge only once. Then I add some grain to the tun, sac rest again with enough volume to no sparge for my second beer.
If I decide to sparge, after collecting enough wort for a full boil on beer number 2, I feel I can get a few more gallons to make a small batch of small beer without worrying about tannins.
My reasoning is this, I haven't sparged the crap out of my grain yet, and I also haven't raised the grainbed over 170. Also, I have some 'fresh' grain in there, with fresh and active enzymes ready to go to work.
I have pulled a third beer a few times before, without a tannin problem. The problem I did have consistently was low gravity. So if I boil longer on beer 3, I can evap more water and get my gravity at the expense of volume.
I don't decoct when I do this method, if I did who knows? Possibly I could get tannins.
The reason I brew this way sometimes is to get more bang for my buck in terms of time spent brewing. I can get 2 awesome beers @ five gallons each and a third mild at around 3 gallons and it takes Mr about an hour and a half longer than a single 5 gallon batch.
With a baby and 2 older kids, my time is very expensive. Lol
I need to make the most of it, and so far, its working out very well for me.