Extraction Efficiency and a Dead Horse

Hey all.

I apologize, I know efficiency is one of those topics that has been extensively covered, explained, etc. I have a situation that I haven't seen brought up in my readings.

The short:
I have 8 all grain batches under my belt. On every one of those batches, my post boil gravity has been 1.053-1.057.

The odd part:
The estimated post boil gravity of the recipes have been more widely varied. No matter what the grist, I end up with the same post boil gravity. This puts my %'s all over the place, from 50% to 70% at best.

Background:
Full volume, no sparge, single 60 minute infusion at 154-156, eBIAB, Bag Squeezer.

Grains bought pre-crushed from Brewmasters Warehouse.

Grist have been from 10lbs to 18lbs with mostly dark beers.

Using generic spring water from Stop and Shop without any chemical alterations.

Yesterday, I tried mashing out with no additional points to post boil SG.

--------------------------------------------------------------------

I know I should relax, which I am. I know I shouldn't chase efficiency, which I am. I'm going to look into water chemistry as my next course of study.

This is the fun part. Looking at perceived problems, and trying to solve them.

So...any ideas on how to improve extraction? Step mashing? grinding my own grain? 90 min mash (tried once, no difference)?

I'd start by milling my own grain. Since BIAB typically produces a lower efficiency many people will grind their grain a lot finer than you can with a traditional mash/sparge as there is no concern for a stuck sparge.

You will also be able to achieve consistency in that part of the process! This alone should help you on your way to being more efficient and consistent

+1 to milling your own grain

Two things come to mind. First, you have to recognize and account for efficiency dropping proportionally to grain bill size. Even with squeezing, the grain will hold a fixed amount of liquid. The other thing is that given a full volume mash, there may be some grain bills that require up to a 90 minute mash if they are high in non-diastatic grains. The more roasted/crystal/flaked grains you have by percentage, the longer the enzymes from the base grain has to work. (get yourself some iodine to check for full conversion).

Thanks! Picking up a mill today, and will give the iodine test a try next time.

I recommend leaving the dead horse out of your mash. The decomposition enzymes may be interfering with the amylase, killing your efficiency.

Since it has no starches that need conversion, you can always add the carcass after the mash while you're bringing it up to a boil. This is known as first wort horsing, but you'll usually see it referred to as FWH around the forums. It's an old technique, but it seems to be experiencing a renaissance of sorts.

zeg said:

I recommend leaving the dead horse out of your mash. The decomposition enzymes may be interfering with the amylase, killing your efficiency.

Since it has no starches that need conversion, you can always add the carcass after the mash while you're bringing it up to a boil. This is known as first wort horsing, but you'll usually see it referred to as FWH around the forums. It's an old technique, but it seems to be experiencing a renaissance of sorts.

Click to expand...

^^This

Bobby covered extraction dropping with grainbill size, but another thing you may want to consider is adding a dunk sparge in another vessel. I know it adds a step to the dead-simple BIAB process, but no-sparging amplifies the loss of efficiency as your grist weight increases. I BIAB + dunk sparge and get very high and (more importantly) extremely consistent efficiency.

I was going to suggest a sparge, but daksin beat me to it. All other things being equal, sparging will increase your efficiency without increasing your boil volume.

zeg said:

This is known as first wort horsing

Click to expand...

Hilarious!

Thanks for the help guys! I'll try leaving the horse out of the next mash. That may be why I'm getting off flavors...