Evaluation of grain crush

[hlmbrwng]

Our last brew was an imperial stout. It was our first all-grain brew. Shooting for an OG of approximately 1.120, we had plenty of grain in our mash. I was not expecting a high efficiency, but what we got was pretty damn low. Somewhere under 60%. Depending on which calculator I use, it is either about 60% or 54%. We needed to add a lot of DME at the end of boil to hit our target gravity.

We are using a rectangular cooler with a copper manifold for a mash tun. Single-infusion mash (held 60 minutes), with batch sparge (held 15 minute). The pre-boil volume was on target.

I even showed my brew diary, in which I write every detail down, to the LHBS employees and they said that everything appeared right. I even talked to them about the water profile, pH and all. They said the only thing that they could think of is that it was a problem with the grain crush.

For our next brew, we ordered from the same online store (I am withholding the name so that I can get an unbiased opinion about the crush - and if there is an issue I will talk to them about it). This time I took photos of the 2-row malt. I grabbed a handful of grain, separated out the grains that were still whole, and calculated what percentage of the grain they made up. Of course, this does not account for the finely crushed grain that is at the bottom of the bag, so the calculation is probably off a bit.

If a grain was crushed at all, I considered it part of the weight that was crushed. For a handful, I got 9.8 grams of crushed grain and 0.9 grams of whole grains. Total: 10.06 grams, with the uncrushed grain making up 8.9% of the total weight.

What do you think?

Photo 1: Handful of grain

Photo 2: Close-up

Photo 3: Separation of grain

Photo 4: Uncrushed grain

 

[Wolfhound180]

The crush looks okay to me. I have my own mill and condition my grains, I like a pretty fine crush. With a huge beer much efficiency is lost due to usually using a very small amount of sparge water. That's my experience though. I just adjust my recipe accordingly for those big ones.

 

[schematix]

That doesn't look like a crush to me at all. I'd call that 'cracked'.

Ideally you want to see as many whole husks as possible, and small pieces i'd describe as around the size of very course ground pepper. Nothign should be uncrushed.

What you have is trash and i'd be pissed.

 

[specharka]

Gonna need some more information on this one for troubleshooting. What was your grainbill size? Mash volume? Temperature?
It's also worth noting that there are theoretical limits for batch sparging efficiency based upon the wort volume. Take a look at the following calculator, and you will appreciate how difficult it is to hit your ridiculous OG.
http://seanterrill.com/2013/10/05/batch-sparging-calculator/

 

[hlmbrwng]

Gonna need some more information on this one for troubleshooting. What was your grainbill size? Mash volume? Temperature?
It's also worth noting that there are theoretical limits for batch sparging efficiency based upon the wort volume. Take a look at the following calculator, and you will appreciate how difficult it is to hit your ridiculous OG.
http://seanterrill.com/2013/10/05/batch-sparging-calculator/

I've tried responding to this post 3 times, and each time I erase what I wrote because I notice something strange in my estimates using Beersmith. I'm not sure if my recipe was changed accidentally, if I copied the estimates incorrectly when I wrote them in my brew log, or...I don't know. I will post a detailed account of what I did and what I was expecting to get for efficiency as soon as I can make sense of this. Thank you for your response.

 

[bonecitybrewco]

Terrible "crush" in my humble yet honest opinion. Brutal. I wouldn't be paying any extra for that. I know it's harsh but when you are paying extra for them to crush it, you at least expect a half decent effort. That's just bad. I'd be buying your own mill for that big of a grain bill if it's a regular rotation anyways, but still. That's what I would call taking advantage of a customer.

 

[kh54s10]

I wouldn't say terrible crush. But I wouldn't say it is very good either.
You don't say what OG you ended up with. I would say the crush was responsible for some of the low efficiency, but not all of it. The couple of high gravity brews that I have tried came out lower than average beers. With really high gravity brews it is difficult to get as good efficiency as normal.

 

[Smellyglove]

I'd say it to coarse. It depends on your system and what it can handle though. If I'd gotten that crush in my bad I'd mash longer.

But on the other side. I'd say the crush has mostly an impact on the rate at which you get the conversion. I recirculate, that might be why I'm saying this- but I've never gotten far off target due to the crush. It takes longer to convert, but you'll convert it is my experience.

Lower OG on high gravity beers has nothing to do with the crush.

 

[hlmbrwng]

Gonna need some more information on this one for troubleshooting. What was your grainbill size? Mash volume? Temperature?
http://seanterrill.com/2013/10/05/batch-sparging-calculator/

This thread is actually shedding more light on possible errors in my calculations than anything else. I'm glad I asked the question.

10 lbs Munich malt
4 lbs 2-row
2 lbs roasted barley
2 lbs chocolate malt
0.5 lbs black patent malt
0.5 lbs barley, flaked


10.5 gal rectangular cooler as mash tun, has copper manifold with good coverage of bottom of tun
6.56 gal mash in @ 164.5 F —> target temp 152.5 F (held for 60 min)
Added grain to water, mice well
Recirculated wort until clear
Drained fairly fast

2.93 gal batch sparge @ 168 F (15 min)
Mixed well
Drained fast


My estimate for pre-boil volume much lower than what I got.
The estimated pre-boil volume was: 5.87 gal
I ended up with: 6.75 gal

Obviously, at this point the gravity is going to read low. We boiled down the volume to about 5.5 gal (was aiming for roughly 5.87 gal to compare against the estimated vol. - I took my eye of the wort for too long I suppose) and took a gravity reading. Allowed the wort to reach room temperature; measurement made with refractometer. Measured gravity 1.086.

I just used a separate online efficiency calculator, and for an estimate of 75% efficiency, the OG is 1.089. In agreement with the new estimate through BeerSmith.

I am now rechecking my calculations. I may have entered something incorrectly into BeerSmith. Originally, I wrote down that the expected pre-boil OG was 1.102 (assuming a "brew house" efficiency of 72%). But now going through the estimates again, I get 1.086 for this same estimated efficiency of 72%. Although I measured at 0.3 gal less than the 5.87 gal vol. estimate, it sounds like the gravity was pretty damn close to the OG estimate.

One thing I should repeat though is that the grain in the photo is for a beer that has not been brewed yet. I suppose it's possible that the crush is different. I still appreciate the opinions on the crush, because I don't have a good eye for it yet.

 

[MagicMatt]

I'd still recommend getting your grain crushed elsewhere. Buying a mill was one of the best purchases I've made to increase efficiency.

This is what a good crush should look like. What you have is just cracked, not crushed.

 

[hlmbrwng]

I'd still recommend getting your grain crushed elsewhere. Buying a mill was one of the best purchases I've made to increase efficiency.

This is what a good crush should look like. What you have is just cracked, not crushed.

That definitely looks a lot different from mine. This is part of the response I got from the company.

"The majority of grain in a good crush should have two things - exposed endosperm and an intact hull. That appears to be the case with your grains, so I would call that a good crush. You will of course see some less crushed, but even some of the whole grains that snuck through I can see some exposed endosperm."

I don't know. I guess what I need to do is brew with it and determine the efficiency. Then I'll go from there. Hopefully, one day I'll be using my own mill.

 

[bonecitybrewco]

I think their answer is bogus and is very telling of their customer service level.

 

[kh54s10]

$20-$30 Corona style mill. It will give you consistency, even if not quite as good as a $200 roller mill might.

It also allows you to buy uncrushed grain which will last longer than crushed, then you are able to brew when you want, not when you can get to the lhbs or an online order to arrive.

 

[j-hemmie]

Getting a grain mill was one of the best investments I've ever made for homebrewing. My efficiency shot up dramatically since I began crushing my own grain. If you want an economy model, look for the Cereal Killer mill. This time of year brewstores will typically offer them up at under $100 shipped.

 

[mabrungard]

Yah, cracked. That is all the OP's milling is providing. It's not sufficient. The result that MagicMatt is showing is what I normally produce. You need to see some flour in the crush. I condition my malt before milling a obtain a high percentage of flour along with nearly intact husks. The bed still flows well in my RIMS.

 

[Smellyglove]

My guess is that they need to let more grains in on the rollers, or make the rollers go faster.But those whole grains on the side also suggests they need to tighten the gap a bit. That's to many whole grains on that plate.