Efficiency Issue: Poor Conversion or Too Much Loss?

[MrEggSandwich]

New to all grain, have the Blichmann BrewEasy. I'm not all that familiar with calculating efficiency, and I do not expect very high efficiency with this system, I do know this: I need to do better.


Use Brewer's Friend for my calcs...I am still tweaking the settings. I have been setting my batch size to 8.5 gallons to get 6.5-7 gallons into fermentor.

Last week, I brewed a big chocolate stout with 31lbs of grain....15 gallon mash tun can't hold all that much more grain. Started with 14.5 gallons of water, and ended up with around 7 gallons of 1.068 wort (1.076 target) into fementor (44%).

The batch before that was an IPA where I was targeting 1.070 (26lbs grain) and I hit 1.068 (6.25 gallons into fermentor)...Brewer's Friend has me at 69.2% conversion, 41% brewhouse).

I'm confused at why my brewhouse % was lower with the IPA?

Last 4 batches according to Brewerfriend:


Brewhouse Conversion
49 68.7
42 64.1
41 69.2 (IPA)
44 58 (Stout)


So- Am I just leaving too much behind? Or not getting good conversion?

Both? What should conversion % be?

 

[day_trippr]

Generally, extract efficiency goes down with increasing grain bills.

Dead loss shouldn't change, and if you're batch sparging (I don't know anything about how the BrewEasy works) then channeling is essentially a non-factor.
Don't know why the smaller beer had worse efficiency though.
Do you crush your grains or buy them crushed?

Cheers!

 

[Biscuits]

One red flag I see is that you're starting with 14.5 gallons of water and ending up with 6.5-7 in the fermentor? That's insane loss! Thats like saying you're losing more than a gallon from each the mash tun, the kettle, boil, and fermentation!
I would start with the easiest to figure out first....boil-off. Throw a few gallons in and start a rolling boil...let it go for 15 or 30 minutes, cool it down, and measure ho much you lost and multiply it by whatever you need to calculate a 60 minute boil loss.
After that you need to start paying close attention to your volumes as you move from mash to kettle to fermentor and how much gets bottled.
I'd say based on an off the top of my head analysis of your water to grain ration in that recipe, you're getting much higher conversion than you think, but something is not right with your process...you are having a lot of loss(es) going on somewhere that need to be accounted for and corrected. with 14.5 gallons of liquor, even with a gallon loss at each step, you should still be putting 8.5 gallons into the fermentor, but you're putting in even less than that.

 

[RM-MN]

New to all grain, have the Blichmann BrewEasy. I'm not all that familiar with calculating efficiency, and I do not expect very high efficiency with this system, I do know this: I need to do better.


Use Brewer's Friend for my calcs...I am still tweaking the settings. I have been setting my batch size to 8.5 gallons to get 6.5-7 gallons into fermentor.

Last week, I brewed a big chocolate stout with 31lbs of grain....15 gallon mash tun can't hold all that much more grain. Started with 14.5 gallons of water, and ended up with around 7 gallons of 1.068 wort (1.076 target) into fementor (44%).

The batch before that was an IPA where I was targeting 1.070 (26lbs grain) and I hit 1.068 (6.25 gallons into fermentor)...Brewer's Friend has me at 69.2% conversion, 41% brewhouse).

I'm confused at why my brewhouse % was lower with the IPA?

Last 4 batches according to Brewerfriend:


Brewhouse Conversion
49 68.7
42 64.1
41 69.2 (IPA)
44 58 (Stout)


So- Am I just leaving too much behind? Or not getting good conversion?

Both? What should conversion % be?

I'm expecting my conversion percentage to be somewhere in the 90's but I mill my own grain and since I do BIAB I mill it very fine. For you to get that low of conversion your grains would hardly be cracked or you mashed for too short of time. Look carefully at the grains to see how they are milled.

With that large grain bill your brewhouse efficiency will take a hit but not down to 41%. Figure out where your losses are. Do you have wort left in the mash tun? Did you leave a lot of trub in the boil kettle? Did you leave wort that wouldn't fit into the fermenter? Somewhere there is a lot of loss.

 

[chickypad]

The others are right those losses sound like way too much, with that much starting water you should have more like 10 gals in the ferementer. You really need to do some good measurements and find out where these losses are coming from.

As far as conversion, I don't use Brewer's friend but they seem to describe conversion efficiency in an odd way. I take the first runnings gravity and use Kai's simple formula with table to estimate conversion efficiency (about half way down the page in the article linked below). As RM-MN says that should be in the 90's, if not you need to work on that, with crush usually being the first thing to check.

Troubleshooting Efficiency

 

[MrEggSandwich]

The others are right those losses sound like way too much, with that much starting water you should have more like 10 gals in the ferementer. You really need to do some good measurements and find out where these losses are coming from.

As far as conversion, I don't use Brewer's friend but they seem to describe conversion efficiency in an odd way. I take the first runnings gravity and use Kai's simple formula with table to estimate conversion efficiency (about half way down the page in the article linked below). As RM-MN says that should be in the 90's, if not you need to work on that, with crush usually being the first thing to check.

Troubleshooting Efficiency

Awesome. Thanks guys.