BIAB small beers: over-extraction?

eulipion2 · 02-11-2010, 07:53 PM

Hello,
I'm looking at getting into both Brew-In-A-Bag and No-Chill methods, and I really want a nice mild for this spring/summer. Would doing a full 5-gallon batch (~7.5 gallons in the mash) over-extract the grains of a small beer such as mild or ordinary bitter?

Thanks!

**david_42** · 02-11-2010, 08:33 PM

Over-extract? Not in any way I understand the term. Once you've got all of the sugars out, that's it. Tannins aren't a problem with this method. I've got a nice OB on tap, that I brewed using the method. The Dark Mild I made for the Septembeerfest, was consumed with few complaints. None, if you toss out the, "It's not hoppy enough" ones.

Hermit · 02-11-2010, 08:56 PM

I just did my first and have a calculated efficiency of around 75% if you toss out the fact I ended up with about a gallon more than planned. I 'erred' on the high side with the liquids to say the least. Rounded up here and there, etc. Plus set the grain bag aside and caught the runnings for a while. I boiled full blast for the last 20 minutes or so and still have about 1 gallon too much, but my figures OG was right on.

So, yeah, I 'over extracted'.

eulipion2 · 02-12-2010, 01:12 AM

Sorry, I've read in other places "over-extracted" to mean leaching out tannins. Why isn't this a problem with BIAB? I'd think with such a thin mash it'd be much more likely.

Hardleft · 02-12-2010, 01:54 AM

You can always reduce the amount of mash water and sparge in another pot, as DeathBrewer teaches. You could also add the sparge water after the 60 minute mash, so that you would only be exposing the grains to a large amount of water for a short time.

eulipion2 · 02-12-2010, 02:04 AM

Hardleft, I think I like the "add after mashing" option, but could that not still wash out tannins? Would it be better to remove the grains before adding the additional water?

Hardleft · 02-12-2010, 02:11 AM

I think that you will be fine either way. I would (and please realize that I am no expert in any sense of the word) remove the grains, add the sparge water and heat it up to 175. Then dunk the grains in there for 10 minutes. That way you are rinsing the sugars out and doing the mash out step.

I dont really know why a mash out is done, but it seems to be popular...

Seriously, I would check out DeathBrewers threads on stove top all grain and partial mash. He would know far more than I.

bakins · 02-12-2010, 02:16 AM

Don't bother with the sparge. Just use all the water in the mash. It should be fine. I haven't sparged in well over a year. Big beers,small beers and everything in between.

**Reelale** · 02-12-2010, 02:28 AM

Quote:

Originally Posted by eulipion2

Sorry, I've read in other places "over-extracted" to mean leaching out tannins. Why isn't this a problem with BIAB? I'd think with such a thin mash it'd be much more likely.

Tannins are a function of pH. Since you are using all of your water volume in the mash, the wort pH doesn't change like it would with the addition of fresh sparge water. This is assuming of course your mash pH is good.

Synovia · 02-12-2010, 03:19 PM

Quote:

Originally Posted by eulipion2

Sorry, I've read in other places "over-extracted" to mean leaching out tannins. Why isn't this a problem with BIAB? I'd think with such a thin mash it'd be much more likely.

Tannin extraction happens for 1 of 2 reasons:

Mash/Sparge PH gets too high
Mash/Sparge Temperature gets too high.

Unless you're doing a couple rounds of sparging, you're not going to exhaust your grain's PH buffering capacity.