Grain Crush?

First brew this coming weekend on upgraded system...
First time BIAB...

What crush is recommended for traditional BIAB (no recirculation)?

I've seen threads where people are recommending .045 or coarser for recirculating BIAB, but not seeing any recommendations for BIAB without recirculating...

r8rphan said:

First brew this coming weekend on upgraded system...
First time BIAB...

What crush is recommended for traditional BIAB (no recirculation)?

I've seen threads where people are recommending .045 or coarser for recirculating BIAB, but not seeing any recommendations for BIAB without recirculating...

Click to expand...

You'll get various mill setting opinions, but I BIAB with no recirc except the occasional paddle stir during mash. I have a Kegco 3 roller mill and I grind pretty finely....I haven't measured with a gauge, but I am about .035 on the roller settings. I'd call this a medium fine crush, and I get very good efficiency numbers with this setting. It is fine but not baby powder fine.

I have both Wilser bags and an Arbor Fab mesh 400 micron basket. Both give me good straining, plus I strain trub thru a 5G paint strainer bag into fermenter. It all settles out in the yeast cake anyway.

Set your gap to "flour".

I have a wilser Bag (400 micron) and a Brew Bag (250 micron), was thinking of trying the brew bag first since it's custom made for my keggle..

How much stuff is captured by the paint strainer bag? That's an interesting idea..

TexasWine said:

Set your gap to "flour".

Click to expand...

I don't have that feeler gauge.... lol

Set your gap with a credit card (~.032") and you'll be fine.

LLBeanJ said:

Set your gap with a credit card (~.032") and you'll be fine.

Click to expand...

For BIAB you want a bit thinner than a regular CC (0.032"). I use the American Express junk cards they sent in the mail (0.026").

You could sand some off a regular one...

I just did a non-recirculating BIAB brew with a mill gap of .024". I came in at 83% mash efficiency.

Agree on the gift card gap test.I have no idea of the micron of the bags but wilser bags are the way to go with the grain.Good efficiency with no grain crud in the wort.No complaints

ch19 said:

I just did a non-recirculating BIAB brew with a mill gap of .024". I came in at 83% mash efficiency.

Click to expand...

Did you do anything to try to further extract wort/sugars after you pulled the bag from the kettle (ie, squeeze, dunk, rinse with water, etc.)?

I mashed with almost the full volume, stirred every 15 minutes, pulled and squeezed the bag, poured over 3 litres of hot tap water and squeezed again.

r8rphan said:

I have a wilser Bag (400 micron) and a Brew Bag (250 micron), was thinking of trying the brew bag first since it's custom made for my keggle..

How much stuff is captured by the paint strainer bag? That's an interesting idea..

Click to expand...

Concerning the paint strainer bag: They are cheap like $2.99 for 2 5G strainer bags in the paint section at Lowes. They have an elastic band that stretch over a 6.5G fermenter bucket opening. Be sure to sanitize and pour cooled wort thru to let the bag strain out some of the break material in your wort. I usually collect 1 to 2 cups of trub to toss. Some folks don't do this as these break materials will settle out in the yeast cake. But this is simply one step closer to cleaner beer in my opinion. Rinse strainer bag, dry and reuse. I have one I have used several dozen times.

Squeeze the bag? Yes, at least I do...extract all the goodness you can from your wort. This is your fermentable (sugars) you are squeezing out to the last drop. My Arbor Fab has a heavy press plate I use, and the Wilser bags get a good old fashioned squeeze til it runs close to dry. I hear some folks hollering "astringency" issues caused by tannins in the grain hulls. I've never had this issue, and with 80+% efficiency in many cases, I see no reason to change.

A fine grind and good squeezing will give you good results.

My LHBS told me they can't change the mill gap. Because I don't have a mill, my only option is LHBS running grains thru mill twice and my efficiency stays over 75%. Not bad for such a simple BIAB setup, I'm happy!

r8rphan said:

I have a wilser Bag (400 micron) .

Click to expand...

Where did you get this information? I thought most all polyester voile was approx. 200 - 300 micron?

wilserbrewer said:

Where did you get this information? I thought most all polyester voile was approx. 200 - 300 micron?

Click to expand...

Maybe he is thinking it is the same micron size (400) of the Arbor Fab mesh baskets where you can select various screen sizes of your choice?

FWIW I milled my grains at 0.035" for my last batch and got pretty poor efficiency. I'm going to try 0.025" for my next batch.

I mill my grain to .030, mash at a thickness of 1.75 qt per pound then do a dunk sparge in a bucket with the rest of the needed water and squeeze the bag firmly to extract all the goodness. This consistently gives me mid 80s efficiency with beers that are 1.050 to 1.070 SG.

wilserbrewer said:

Where did you get this information? I thought most all polyester voile was approx. 200 - 300 micron?

Click to expand...

I dunno.. Thought I got it from your website, but could be wrong...

Whatever it is, that's what I got.. lol

So I crushed my grains this morning...

I have a Crankandstein 3D... (for some reason I thought I had a monster mill)

Last night I was trying to get info on adjusting it, seeing as it's been like 3 years since I used it, and probably 5 or more since I bought it, but could find none... Why don't they have documentation on their website??? Grrrr...

I 'thought' I had the 2D, so trying to measure gap between the two rollers was useless.. So this morning I measured out my grain bill, then I set it to the middle of the detent selections (which is where I think I used to have it)..

After crushing there, I just trusted my little plus and minus signs I had drawn on in pencil on the thing, and set it to what I believed to be the smallest crush and ran all the grains through a second time...

Only after running all the grains through the second time, and turning the whole assembly over to brush the flour off of the mounting plate, did I notice the third roller..

DOH! I guess that's where I should have been trying to measure the gap!

Oh well... It'll probably be just fine.. We'll see what happens.. But there's lots of flower and all the hulls seem to be pretty torn up... Hope that doesn't inject any bad stuff (ie tannins) into the wort...

Anyways, it's a done deal, today is brew day, I have the water ready, the system set up, the grains ready and as soon as I finish this cup of coffee, I'm getting dressed and doing my first brew on the new system...

Pray for me!

r8rphan said:

Oh well... It'll probably be just fine.. We'll see what happens.. But there's lots of flower and all the hulls seem to be pretty torn up... Hope that doesn't inject any bad stuff (ie tannins) into the wort...

Anyways, it's a done deal, today is brew day, I have the water ready, the system set up, the grains ready and as soon as I finish this cup of coffee, I'm getting dressed and doing my first brew on the new system...

Pray for me!

Click to expand...

Next time maybe try searching for images of crushed grains to get an idea of what it should look like, then testing a handful at a time. A lot of BIAB brewers will double crush to be sure.

I don't think I've seen any off flavors associated with too fine a crush. AFAIK you can't crush too fine with non-recirc BIAB.

pretzelb said:

Next time maybe try searching for images of crushed grains to get an idea of what it should look like, then testing a handful at a time. A lot of BIAB brewers will double crush to be sure.

I don't think I've seen any off flavors associated with too fine a crush. AFAIK you can't crush too fine with non-recirc BIAB.

Click to expand...

Oh this has a 'lot' more flour than what is typical....

I exceeded my expected efficiency some, which means I get an extra 3/4 gallons of beer from this brew! So as long as there are no off flavors from the shredded husks, then I done good...


What I did wrong was misremembered evaporation rate, so now I gotta sit an extra hour and a half while I boil off the excess water so I can start my hops additions... Oh well, live and learn...