BIAB: Crush and Efficiency

I know that double crushing your grains - that is to say, milling the grains twice - is said to yield a greater brew-house efficiency. But what kind of efficiency do you get if you only mill it once?

50% ? 60% ? 70% ?

Anyone out there only do one crush?

My understanding is that it is not good to over-mill your grain. I've always just run it through the mill one time, and get 80% efficiency if I'm doing a 6-gallon batch, and over 85% if I'm doing 15 gallons or more. The efficiency goes up on my system with larger batches, for some reason...I suspect mash tun dimensions.

Anyway, it seems I get good mash results from keeping temp constant/accurate, having the right grain/water ratio, ensuring no dry spots/clumps in grain (add grains to mash water slowly, good initial stir), and doing a good sparge. For a batch sparge, I drain the first runnings, then use 169F water and let it sit for 20 minutes, then drain that.
I got a bit better efficiency when I started using a march pump to continuously recirc the mash water, so there's a constant flow through the grain bed.
IMO, I would not double-crush the grain. Seems like over-crushing has the potential for a 'stuck mash', which is far worse than a couple points of efficiency you might get.
Cheers

No worries about a stuck mash with BIAB.

That being said, I have found that there is no appreciable difference in efficiency between a fine single crush and a standard double crush. I am a BIAB'er and this opinion comes from several experiments with different crushes over the course of the past few years, not hearsay or repeating second-hand "facts" (no offense intended to zakleeright). I currently use a corona mill and tear those little grains up pretty good with it.....get a consistent 83-83%.

>>That being said, I have found that there is no appreciable difference in efficiency between a fine single crush and a standard double crush.

I agree. But I think the concern is one doesn't always get a "fine" single crush, thus the suggestion to double crush.

The only danger of over crushing is you may end with more dust flowing out of the bag, into the wort, and becoming trub.

Agreed, especially if you are at the mercy of someone else to crush your grain. I do all my own crushing and have experimented with both single and double crush, fine vs course crush, and roller vs corona.

Ah, ok. Thanks for the input guys. I guess I'll have to brew more and find out for myself. Darn!

I had read a few threads on here advocating the double crush, but when I phoned up my LHBS they had no idea what I was talking about. Or, they did know what I was talking about, and played dumb so they didn't have to clog up their mill.

I recently got 77% efficiency from my first all-grain attempt. The grains were crushed (I assume single crushed) by Northern Brewer and I did it as a BIAB with sparge. It didn't seem to be an excessively fine crush.

I am consistently getting 83-85% eff. with BIAB using Northern Brewer's standard crush. My setup is a 44q. Bayou Classic w/ the strainer basket and a 5 gallon paint strainer bag. I don't sparge but I do mashout at 170 for 10 min. and give a firm squeeze by pushing down w/ a pot lid on top of the grains several times. I lose .05 gal/pound of grain. I have to recalculate recipes based on this efficiency and end up using a fair bit less base grain. Hooray I saved a few bucks on base malts... but really I am wondering... am I losing some flavor too by using less base malt? Does anybody know? Whats the downside to this increased efficiency?

I was using Austin homebrew standard crush and got about 70% efficiency pretty consistently. I bought a monster mill and started crushing my grain myself and set the gap to just allow a credit card AND the numbers to fit through. Even with it set that far apart, I got a very fine crush and dust. On the two batches I did with that, I got 80% efficiency but almost a gallon worth of trub. I am going to try to crush the grain much slower thinking that the drill we used just spun to fast and tore up the grain instead of just crushing it.

Sadly no. Two homebrew supplies here in town, neither crush their own grain or sell grain mills. Closest one that does (here: http://www.homebrew-supplies.ca/via...ch_category_id=118&search_string=&search=+Go+ ) is about an hour and half away and charges exorbitant prices: ($164.85 - $242.85), handles sold separately 30 bucks-ish, plus gas to get there..... I'm looking to move to all grain, currently working fixing a leaky bulkhead on my mash tun. So I thought I'd get a jump on BIAB, at least to get my feet wet. But Not at those prices... I'd rather account for 55-65% efficiency and kick in a few extra bucks for more grain.

For the question: "am I losing some flavor too by using less base malt? Does anybody know? Whats the downside to this increased efficiency?"

If you hit target gravity you are golden. The thing to focus on is the percentages of the recipe. If the original recipe was 80% base malt and 18% Crystal 120, and 2% debittered black, just try and retain those ratios...if you only decrease the base malt, your recipe will be off.

As long as you do this, the only "downside" to increased efficiency is MORE BEER!!
The homebrew community is a generous crew, and any of us are willing to take this extra brew off of your hands!

Yeah funny... I posted (above) that I was consistently getting 83-85% with N. Brewer's standard crush... and then I went to brew Jamil's West Coast Blaster yesterday. When I looked at my grains they just looked less crushed than usual with less flour in the bags too. Lo and behold I got 74% efficiency and had to add a pound of DME preboil. No big deal except I cant get any consistency to my process this way. There may be a mill in my future.

The thing to focus on is the percentages of the recipe. If the original recipe was 80% base malt and 18% Crystal 120, and 2% debittered black, just try and retain those ratios...if you only decrease the base malt, your recipe will be off.

Click to expand...

Goes to show you I don't know what I don't know. How can I expect the recipe to turn out since I only adjusted the base malt? So this means that the specialty grains contribution depends on the relative quantity of base malt and not the batch size? I learned it's the other way around but maybe I learned wrong... so... How does this work?

Using AHS's standard crush would yield 70%-75% with a BIAB and a few gallons of sparging. Using AHS 'double milled' or my corona mill yields 80%-85%.

Now without sparging, take 5%-10% off.

Yes, I think I am going to just account for a 60ish percent efficiency. I'm going to do a no-sparge BIAB brew this weekend.
My plan for Pale Ale

Recipe Type: All Grain
Yeast: us -05
Batch Size (Gallons): 3.3 (I plan to lose .3 -.5 Gallon to trub)
Original Gravity: 1.056 (Predicted)
Final Gravity: 1.014 (Predicted)
Boiling Time (Minutes): 60 minutes
IBUs: 75
Color: dark Golden
Primary Fermentation (# of Days & Temp): 21 days at 66-68 degrees
Secondary Fermentation (# of Days & Temp): none

6.25 lbs of 2 row
1.25 lbs of Vienna
0.50 lbs of Carapils
0.50 lbs of Crystal 120 ( I am using 120 because I have it left over)

Hops:
1oz Magnum - 60
1oz Cascade - 30
1oz Galaxy - 10
1oz Galaxy - 1

Yeast Safale US-05

Final Thoughts?

As stated previously, you can go with a very fine crush for BIAB. If you mill your own, set the gap for the crush you want and you are done. If you are having it milled elsewhere, there is a good chance that they will not adjust the gap for you to get a fine crush. In that case, ask them to double crush.

jeffmeh said:

As stated previously, you can go with a very fine crush for BIAB. If you mill your own, set the gap for the crush you want and you are done. If you are having it milled elsewhere, there is a good chance that they will not adjust the gap for you to get a fine crush. In that case, ask them to double crush.

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I don't mean to sound unappreciative, but I already know this information and have demonstrated knowledge of said information in the first post.

The LHBS seems unwilling to discuss double crushing as a possibility, and simply played dumb when I inquired about it.

I cannot afford a grain mill at the moment because....



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Seriously, check the link I posted above to the closest LHBS that sells grain mills and keep in mind I would have to pay shipping or drive and hour and a half to get there.... They sell the handle separately for pete's sake.

But I want to know whether or not, assuming rest of my brew day goes well, that a 60% efficiency is a safe bet based on default crush and the recipe posted above?

The last two brews I've done I've managed to get over 80%
I'll grab a pic of the crush next time I do a beer, but all in all I"m stoked at getting anything over 70% in a bag!!!

jwalk4 said:

I don't mean to sound unappreciative, but I already know this information and have demonstrated knowledge of said information in the first post.

The LHBS seems unwilling to discuss double crushing as a possibility, and simply played dumb when I inquired about it.

I cannot afford a grain mill at the moment because....



Uploaded with ImageShack.us

Seriously, check the link I posted above to the closest LHBS that sells grain mills and keep in mind I would have to pay shipping or drive and hour and a half to get there.... They sell the handle separately for pete's sake.

But I want to know whether or not, assuming rest of my brew day goes well, that a 60% efficiency is a safe bet based on default crush and the recipe posted above?

Click to expand...

Gee, your life must really suck when you can't afford a grain mill.

http://www.amazon.com/dp/B000T3ML4G/?tag=skimlinks_replacement-20

This is the kind that I use for BIAB and it will be shipped to your door. With some care, it can be used for conventional all grain too.

RM-MN said:

Gee, your life must really suck when you can't afford a grain mill.

http://www.amazon.com/dp/B000T3ML4G/?tag=skimlinks_replacement-20

This is the kind that I use for BIAB and it will be shipped to your door. With some care, it can be used for conventional all grain too.

Click to expand...

Yes, well, I'm on a student budget unfortunately. Nice to see it on amazon for $30. Thanks for the link. I tried ebay, kijiji, craigslist. nothing under 100 bucks.

rhamilton said:

Using AHS's standard crush would yield 70%-75% with a BIAB and a few gallons of sparging. Using AHS 'double milled' or my corona mill yields 80%-85%.

Now without sparging, take 5%-10% off.

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This has not been my experience with AHB, admittedly with just 2 brews.
I asked that the grain be double crushed, but I don't know if it was, so I will assume it was.

I mashed at 150 for an hour (actually the second time for an hour and a half).
I did stir it in, and restirred it on occasion, even adding some heat to make up for what was lost.
I mashed out at 163 (yes this is too low, but would 168 have made that big a difference?) for 10 minutes.

I squeezed the crap out of the bag.

Then I sparged it by soaking the bag in 2 gallons of water for 5 minutes, stirring it in.

I again squeezed the crap out of the bag.

I got a tiny bit above their expected OG. Call it 1.072 as opposed to the expected 1.07 for 5 gallons.

No where near 80%.

And I have BIABed before.


I do think Sparging makes more than a 5% difference, Id say at least 10% and probably more.

Does this type of grain mill produce more flour?

>>
http://www.amazon.com/dp/B000T3ML4G/?tag=skimlinks_replacement-20

Hey jwalk4

Brewhaven at Southdale and Wharncliffe sells crushed grains. Not sure they are cheapest, but convenient.

ontariobeerkeg in Mitchell, 30 min north also appears to be selling grain, etc now