Graduated to BIAB, struggling with efficiency

GDubs

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I made the move to BIAB 5-6 brews ago. I have been blown away by the results!! My beers have improved in every way but I am struggling with efficiencies in the 66-68% range. To this point, knowing there would be a learning curve, I simply increased my grain bill a bit and accepted a lower starting gravity. I have been doing full volume mashes for 5g batches, squeezing the bag like it owed me money, and only rinsing the grain if I needed to top up to my pre-boil volumes.
After talking to a local fellow BIABer, who had some suggestions on how to increase my efficiencies, I set out yesterday to make a high starting gravity NEIPA utilizing some of his suggestions. According to the recipe builder my target was 1.072SG at a 75% efficiency.

Grain bill for 6g batch
#11- 2 row
#3- flaked oats
#1.5- wheat
#1.5- vienna

Rather than calculating my total volume, I mashed at 1.5qts per pound which left me with just under 5g of wort initially. I then rinsed the grains twice to get to my pre boil volume of 6.75 gallons fully expecting my efficiency to top 70%.
I took a sample of the wort, allowed it to cool, adjusted my hydrometer readings for the temp, an ran it all through the boil off calculator..... 1.060 or a mere 62% efficiency?????

The gentleman who offered his advice reports 80% efficiencies using the same grain mill and municipal tap water that I am using.

Clearly I am doing something wrong.....It could be my technique, could be my math, or it could be how I am using the recipe builder. Any thoughts or insights would be greatly appreciated.


G-Dubs
 
Biggest thing that effects your efficiency for biab is crush. Are you crushing it at the LHBS or on your own?

What temp are mashing at?

Static mash or recirc?

Also, on your latest batch. You had 1.75 gallons more liquid than your recipe called for. Boil it down to 5gal and re measure
 
Is your 66-68% efficiency at the end of your mash, or in the fermenter? I'd be interested in the number at the end of the mash/boil if it's not. Crushing finer was definitely where I saw my biggest single bump in efficiency, but mashing can give you a few points here and there. What are you doing for your mash?

And 66-68% would have been good for me when I started out with BIAB all grain. Improvements came with a few things, but some was just by brewing more. I'm generally around that nice 75% now at the end of the mash/boil.
 
Biggest thing that effects your efficiency for biab is crush. Are you crushing it at the LHBS or on your own?

What temp are mashing at?

Static mash or recirc?

Also, on your latest batch. You had 1.75 gallons more liquid than your recipe called for. Boil it down to 5gal and re measure

I mashed at 152 and never got below 150 taking the lid off to quickly stir every 15 minutes…. No recirculation.
My last batch was a 6gallon recipe with 6.75 gallons pre-boil on a 45 minute boil.
I am using the mill at the local shop. I considered a double grind but with three pounds of flaked oats I opted for one time through the grinder…. I will try a finer grind next batch
 
Is your 66-68% efficiency at the end of your mash, or in the fermenter? I'd be interested in the number at the end of the mash/boil if it's not. Crushing finer was definitely where I saw my biggest single bump in efficiency, but mashing can give you a few points here and there. What are you doing for your mash?

And 66-68% would have been good for me when I started out with BIAB all grain. Improvements came with a few things, but some was just by brewing more. I'm generally around that nice 75% now at the end of the mash/boil.

Mark, i have been getting 66-68% at the end of the boil. As for my last batch, I forget exactly what the gravity was preboil…1.048 maybe? The boil-off calculator and my actual starting gravity at were right at 1.06, which is only around 61%.
Im moving in the wrong direction! Lol!!
 
Sounds like you've still gotta sort out your volumes a bit if you expect a certain final volume in the kettle or fermenter and you finish high this will screw your projected FG.

Continue to mark down your starting boil volume and your final boil volume and adjust this to better hit your target.

Yup milling them grains yourself or asking HB store to double crush will help with extraction in the mash.
 
Doesn't sound like any obvious problems with the mash.

At the moment I'd say pretty much the same as Ben, focus on getting the numbers in your equipment profile accurate. Keep the numbers for a few batches and then see if changing the equipment numbers would have got better predictions.

I'd also look drop your efficiency and spend a small amount more on grains. Then as you get your equipment profile and process dialled in you'll probably find you can slowly increase the efficiency and drop the grains.
 
I have been in discussions with other that do not agree with me, but another biggie is the flaked oats. Flaked oats, at least for me with BIAB, do not convert very well, if at all. I only use 1lb at a time though. If I set them to "non-fermentable" in my software, the numbers get very close to what I expect. After I learned that, a lightbulb in my head went on when designing recipes, and life was much better.
I do have my recipe efficiencies set around 60. This does work as my brew store is at least consistent with the crush. I can predict what it will do. I can make up for some of the alcohol by pitching high and using healthy yeast (another good thing about my brew store, the dates on my yeast are usually WELL within range). I normally will use two packs of yeast for 5 gallons.
Don't worry about a low efficiency at the homebrew level and moving in the wrong direction. Just plan for it and make it consistent.
I think this is the time for quote about don't worry, relax, have a homebrew.
 
Interesting about flaked oats.
I've never used them, but I'll keep this in mind
 
I have been in discussions with other that do not agree with me, but another biggie is the flaked oats. Flaked oats, at least for me with BIAB, do not convert very well, if at all. I only use 1lb at a time though. If I set them to "non-fermentable" in my software, the numbers get very close to what I expect. After I learned that, a lightbulb in my head went on when designing recipes, and life was much better.
I do have my recipe efficiencies set around 60. This does work as my brew store is at least consistent with the crush. I can predict what it will do. I can make up for some of the alcohol by pitching high and using healthy yeast (another good thing about my brew store, the dates on my yeast are usually WELL within range). I normally will use two packs of yeast for 5 gallons.
Don't worry about a low efficiency at the homebrew level and moving in the wrong direction. Just plan for it and make it consistent.
I think this is the time for quote about don't worry, relax, have a homebrew.
Are you mashing the flaked oats with a base (diastatic) malt or using them as a steeping addition, say with extract?

If the former, they should definitely provide gravity points and fermentable sugars. If the latter, they won't.

At least that's my understanding. Though I'm willing to listen. :)
 
Are you mashing the flaked oats with a base (diastatic) malt or using them as a steeping addition, say with extract?

If the former, they should definitely provide gravity points and fermentable sugars. If the latter, they won't.

At least that's my understanding. Though I'm willing to listen. :)
My understanding as well, since they have zero diastatic power of their own and niether does extract
 
Are you mashing the flaked oats with a base (diastatic) malt or using them as a steeping addition, say with extract?

If the former, they should definitely provide gravity points and fermentable sugars. If the latter, they won't.

At least that's my understanding. Though I'm willing to listen. :)
I mash them with the other malt. They are in the same bag with the other ingredients and added at exactly the same time to the strike water. Flaked corn, flaked wheat, flaked oats, I treat them all as non-fermentable in the software. For whatever reason, they do not convert worth a damn for me. It might be BIAB, I don't know. All I know, if I click a box that says "non-fermentable". I get close to what I expect. I did it again for my Pre-Pro Lager with the 1 lb of flaked corn, and it worked correctly.
That is why I'm not going to give anyone any crap for an opinion on this, but I do know what works for me with my very basic setup. Others have different setups.
I actually went through the exact same phase of "Why the hell am I not efficient, and what can I do?"
I made notes, asked a shi*load of questions, and adjusted accordingly. The flaked thing was a couple of discussions I had with other brewstore/homebrew people. It seemed to work. The efficiency thing I let go in favor of consistency. I have really liked the last couple of beers that I made, and I ain't changing now :)
 
I mash them with the other malt. They are in the same bag with the other ingredients and added at exactly the same time to the strike water. Flaked corn, flaked wheat, flaked oats, I treat them all as non-fermentable in the software. For whatever reason, they do not convert worth a damn for me. It might be BIAB, I don't know. All I know, if I click a box that says "non-fermentable". I get close to what I expect. I did it again for my Pre-Pro Lager with the 1 lb of flaked corn, and it worked correctly.
That is why I'm not going to give anyone any crap for an opinion on this, but I do know what works for me with my very basic setup. Others have different setups.
I actually went through the exact same phase of "Why the hell am I not efficient, and what can I do?"
I made notes, asked a shi*load of questions, and adjusted accordingly. The flaked thing was a couple of discussions I had with other brewstore/homebrew people. It seemed to work. The efficiency thing I let go in favor of consistency. I have really liked the last couple of beers that I made, and I ain't changing now :)
Me too, man. My last brew was 58% lol. Lots of crystal and marris otter. It still taste good, so i don't care. If i was brewing 300 gallons it might annoy me, but 5gal?, Just not getting my pants in a twist
 
Buy some Amylase Enzymes usually 250ml will cost $25 that'll convert the SH@t out of everything :D.

Ask pro brewers hey you using exogenous Enzymes in the mash most likely answer will be yes. 1ml ish per kg of grist

But Consistentcy is KING:)
 
There is a simple test to be sure that you have converted all the starch into sugars during the mash. Take a few drops of wort (on a plate, say) and add a single drop of iodine, the kind you get at the drugstore. If it turns black there is still starch left to be converted. If it stays kind of brownish then your mash is complete.
 
I have used enzymes in pumpkin prior to freezing it for a pumpkin beer, but I have never used it in the mash. If I really, really want to convert and/or dry out beer, French Saison yeast works too.
 
There is a simple test to be sure that you have converted all the starch into sugars during the mash. Take a few drops of wort (on a plate, say) and add a single drop of iodine, the kind you get at the drugstore. If it turns black there is still starch left to be converted. If it stays kind of brownish then your mash is complete.
I use this test every brew
 
#3- flaked oats
#1.5- wheat
Your problem may lay here. You have a lot of oats and wheat in the mash, they bring a lot of beta glucan into the mash. Sometimes this is called "gum", but it's a white/gray sludge that shows up on top of the grain with an aggressive vorlauf or recirculation. This will bind itself in the grain bed and cause poor flow, leaving sugar behind.

You can add a small amount to the mash and see if it helps. Typically you would only need 3 grams (@1/2 tsp) for 12-15 pounds of grain. If too much is added, it can make things worse by breaking down too many non-starch polysaccharides which creates a mess.

There are liquid and powder versions of the enzyme. I have used both and prefer the dry powder version because it seems to work better and it's cheaper. I use it with every brew and it improves the flow of the mash. My efficiency was always pretty high, but I went from @ 85% to @ 90%. I also found it makes the mash tun easier to clean because it doesn't have all that sludge stuck to the sides and bottom.

Here's a place you can get the dry version, but it can be found else where too:

https://socohomebrew.com/beta-glucanase-enzyme-1-oz/

The liquid version is sold by MoreBeer and it has a blend of enzymes in it. It supposed to work better that just beta-glucanase alone, but I thought the dry version with the single enzyme works better.

https://www.morebeer.com/products/cellarscience-glucabuster-placeholder.html

Hope this helps!
 

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