Double milling with BIAB

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Grinnan5150

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I have read several threads about double milling the grains for better efficiency with BIAB. The guy at my LHBS said that is not necessary. Does a single crush work just fine or based on everyone's experience here is double milling the way to go?
 
depends on the crush. If there are any uncracked grains or just barely cracked at all...that could hurt. With BIAB a lot of flour is fine, so a finer crush may yield you greater returns. I've been noticing my efficiency does seem to be tied to the crush.
 
Most LHBS set their mill so that 3 vessel brewers avoid a stuck sparge. With BIAB, you don't need to worry about this. Based on my experience, most of the time a double crush improves efficiency. Brew one batch with a single crush and another batch with a double crush and test it yourself.
 
I crush my own, and do a much finer crush than either buying pre-crushed, or having the LHBS crush for me. Definitely better efficiency.
 
Yap, do it twice. It will help. He may not think it's necessary, but you're paying his bills, man. For an extra ~45 seconds of effort, he should be willing to accomodate you. He can advise all he wants, but in the end, it's your beer.
 
If you're BIAB, Increase your mash to 90 minutes and you'll greatly increase your efficiency.
 
I get 75-80% eff from BIAB. Before I had a grain mill, I'd double (or triple) crush at the HBS and got 70-75%. I have my mill set to ~.42 or so, and since I started milling my own grain, I've seen that 5-10% jump in eff. So yeah, for BIAB, the better the crush, the better your eff.
 
If you're BIAB, Increase your mash to 90 minutes and you'll greatly increase your efficiency.

Why?
I usually mash 45 minutes, and an iodine test shows starch conversion is complete. What would be the added benefit of a longer mash?
 
Why?
I usually mash 45 minutes, and an iodine test shows starch conversion is complete. What would be the added benefit of a longer mash?

If there is stirring going on it's possible, I guess, that sugars are being freed from their grains or something I suppose. I too have been mashing for under 60m and getting good results.
 
Why would an additional 30 minutes improve efficiency?

I used to not be a believer of this either, but I've switched to 3-8 hours mashes and have seen my efficiency rise from 72% to 80%. Conversion doesn't completely halt at 60m, especially betas.
 
Since switching over to BIAB from extract, I have double crushed all 3 batches.... I've gotten great efficiency (75+)...but, because of that, I have had higher OG's, and much higher attenuation (85-87% on 05 and Pacman) . . ..perhaps from a thinner mash and more fermentables??
I am dialing in this new system, so for my next batch I will not double crush and see how it goes.
 
Be sure all the grain is well broken and NO whole grains exist...single double triple crush watever it takes to be sure that all the grain pieces are well fractured. A single crush on one mill might very well be a double on another.
 
Just to be clear, are we talking double crush on the same setting (that is, same gap between mills)?
 
I have 7.5 gal kettle. If the double crush gives me better efficiency, this a higher OG. After pulling the bag, leaving 5-ish gallons. I should be able to top off my kettle to hit my numbers for a 6.5 gal bool. Correct????
 
i use a coffee grinder and crush it almost into a flour. works perfectly and a consistent efficiency. easier too because i can buy in bulk
 
Has anyone had experience with a finer grain crush and using a 5 gallon paint strainer bag where some of the grains might have gotten through the strainer and into the wort? I used this method for my first BIAB, but it seemed like some grain particles might have gotten through the strainer while mashing. From reading around, it appears maybe using voile cloth is better for BIAB?

Sorry if this is a little off topic but figured it was close in relation to double milling :)
 
If you're BIAB, Increase your mash to 90 minutes and you'll greatly increase your efficiency.

What is your reasoning behind this? I was under the impression that starch conversion enzymes became denatured at around 45-60 minutes under mash temperatures.

Also, I use a voile cloth bag that I had made and there is still a good amount of "flour" that gets through the bag, leaving a lot of trub.
 
Just to be clear, are we talking double crush on the same setting (that is, same gap between mills)?

I was going to start a new thread but since one already existed... I also have the same question. When double milling for BIAB, does "double crush" mean running it through the mill twice on the same setting?
 
I was going to start a new thread but since one already existed... I also have the same question. When double milling for BIAB, does "double crush" mean running it through the mill twice on the same setting?

It can because the second time through usually crushes the grains more or crushes more of the grains of both. If I had a crusher type mill I'd want to adjust it tighter for the second crush or even the first crush but there are limitations on adjusting the mill if it belongs to someone else and there are limitation on how tight you can adjust the mill and still get it to feed properly.
 
It can because the second time through usually crushes the grains more or crushes more of the grains of both. If I had a crusher type mill I'd want to adjust it tighter for the second crush or even the first crush but there are limitations on adjusting the mill if it belongs to someone else and there are limitation on how tight you can adjust the mill and still get it to feed properly.

I use a BC mill, and do a normal crush for the first pass, and a .010 roller spacing for a second crush. If I go too tight on the first crush, you simply cannot turn the handle, it'll slip on the shaft. If you want to crush fine, you have to do it in two passes.

H.W.
 
I have read several threads about double milling the grains for better efficiency with BIAB. The guy at my LHBS said that is not necessary. Does a single crush work just fine or based on everyone's experience here is double milling the way to go?

I single crush and my gap is set to credit card thickness. My crush looks good and I'm hitting my numbers in Brew Smith.
I guess I could improve my efficiency by double crushing, but I'm not seeing the need at this time to chase numbers.
 
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