Evaluate my crush

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Khirsah17

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I was hoping you guys could take a look at my crush. I am plagued by mediocre efficiency, between 60-67%. I'm trying to figure out if it's my grain crush or my sparging technique. Thanks!

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Why don't you just try crushing finer and see if it helps your efficiency? Is the grain pre-crushed? Mine is usually finer than yours looks...
 
Wow, fast replies. I have a Crankenstein crusher right now, and when it was preset, I think I was getting high seventies efficiency. Of course I had to fiddle with it and now it's worse. I have it set to around 0.39" gap as closely as I could. The cheap model is kinda hard to adjust.

Usually when I sparge, I just add 165F water to the mash tun as needed to keep about an inch above the grain bed.
 
Khirsah17 said:
Usually when I sparge, I just add 165F water to the mash tun as needed to keep about an inch above the grain bed.

That could be your problem right there. You should be sparging around 170-172F...
 
I have a Crank 3 roller model and crush a bit finer than that. I have gone as low as .011", but usually set it at about .02" now. I get a fair bit of flour, but my MLT will handle it. I'm going to crush later today and I'll get a pic for you.
 
In addition to sparing with hotter water, I would suggest to mill finer. From what I can tell, many of the husks still hold endosperm in them which will not be reached by the mash/lauter.

Have a look at the Wiki page Brad suggested and compare it against the pictures there.

Kai
 
Kaiser said:
In addition to sparing with hotter water, I would suggest to mill finer. From what I can tell, many of the husks still hold endosperm in them which will not be reached by the mash/lauter.

Have a look at the Wiki page Brad suggested and compare it against the pictures there.

Kai
I must agree. My efficiency was lagging until I crushed finer. My other issue was alkaline water, but that is for a different post. S
 
I guess I should have mentioned I have the cheapest 3 roller setup crankenstein.

When I look at the pictures on the Wiki, I'd have to say it say it looks somewhere along the lines of the 'poor crush'. I guess for my next brew, maybe I'll try to reduce the roller gap a little bit more. I'm slightly afraid of uneven spacing between the rollers, because of the difficulty of adjusting it, but I'll just have to take my time.
 
Rather than guessing, why not measure the gravity of the last runnings from the sparge?
Collect enough to float the hydrometer at the very end of the sparge. Cool it to a reasonable temperature, take a reading, and adjust for temperature. (Temperature compensation is quite reliable at temperatures below 80F, but gets very unreliable at temperatures in the 150F range.)
If your final runnings have a gravity much greater than 1.010 - 1.015, then look to improving your sparging technique. If they are not greater, then the problem is in the mash.

-a.
 
ajf said:
If your final runnings have a gravity much greater than 1.010 - 1.015, then look to improving your sparging technique. If they are not greater, then the problem is in the mash.

ajf,

I don't think that this will provide you much info for batch sparging and for fly sparging. In batch sparging, if your last runnings are above 1.015 then there is nothing you can do about it. Sure you could sparge more, but only to a certain point since you don't want to extend your boil to long. In fly sparging, the gravity of the runnings will not tell you if you had channeling. This you can only determine by adding lots of water, stiring it and taking its gravity. Basically batch sparging the spent grain to summ up the extract that you didn't sparge.

If his problem is the crush, then there is a percentage of the starches that didn't take part in the mash and won't be convered to extract that can be lautered.

Khirsah17,

You never mentioned if you are fly or batch sparging.

Kai
 
Kaiser,

I am fly sparging. After I recirculate and allow the wort to run clear, I sit next to the mash tun and slowly add water throughout the whole sparging process in order to keep the water 1-2" above the grain. Usually I run it really slow, sparging for an hour or so. I can usually get around 65-67% efficiency.

This last weekend I sparged faster, maybe in 25 mins or so. I only got 61% efficiency. I guess I wasn't super clear on sparging techniques, but apparently speeding things up a bit isnt a good idea if one is fly sparging. I think next time I might try batch sparging twice and see what happens.

One quick question on sparging. I always add hot water around 165-170F continuously to the mash tun. However, in How to Brew, Palmer says, "Mashout is the term for raising the temperature of the mash to 170°F prior to lautering." So does that mean I should raise the temp of the mash to around 170? That means the sparge water I would add would be significantly higher.
 
Does your 3 roller mill have the adjustment bar on it? Mine does and when I mill my grain, I adjust it by sound. I use a corded drill. I start the drill and then while the mill is running I decrease the gap until I start to hear the drill complain a little and then I leave it it there. If I make the gap too small my drill will really complain and stop if I don't increase the gap. I will on occasion mill wheat, rye, and oats and they all require a different setting for a good crush and rather than getting out the feeler gauges I just let my ear (and drill) tell me what the right setting is.
 
Khirsah17 said:
This last weekend I sparged faster, maybe in 25 mins or so. I only got 61% efficiency. I guess I wasn't super clear on sparging techniques, but apparently speeding things up a bit isnt a good idea if one is fly sparging. I think next time I might try batch sparging twice and see what happens.
Yes, the run-off speed for fly-sparging matters for two reasons. A faster run-off encurages channeling as there is a larger pressure difference between the top and the bottom which forces the wort to run faster and by doing so the wort is more likely to seek the path of least resistance. The second reason has to do with concentration gradients between the sparge water and grits of grain. As the low sugar concentration sparge water passes by high sugar concentration grain bits, the sugar slowly diffuses into the sparge water. The faster the water runs by, the less sugar it will be able to pick up and your efficiency suffers.
Try batch sparging and have a look here. Only when you are not satisfied with the theoretical max efficiency that you can get through batch sparging, should you try fly-sparging. The only advantage I see in fly sparging is that its theoretical efficiency doesn't have the limits that batch sparging has, but to get close to that limit you need a darn good fly sparging system.

One quick question on sparging. I always add hot water around 165-170F continuously to the mash tun. However, in How to Brew, Palmer says, "Mashout is the term for raising the temperature of the mash to 170°F prior to lautering." So does that mean I should raise the temp of the mash to around 170? That means the sparge water I would add would be significantly higher.

Yes, he means raising the mash temp to 170, which comes close to the sparge water temp. The idea is to lauter at a temperature that doesn't quite kill the enzymes yet and doesn't lead to excessive tannin extraction. Because the hotter the sparge temp, the easier the sugars are extracted.

Kai
 
Unfortunately I don't have any adjustment knobs on my crusher. I have to disassemble it completely to do it. It's a PITA, I wish I would have spent a bit more money on the upgraded model.

So according to Palmer's equation of raising a mash temp:
Wa = (T2 - T1)(.2G + Wm)/(Tw - T2)

I did a quick calculation based on a recipe I made. If my mash temp was 152, and I had about 11 lbs of grain, I would need to add about 1.5G of boiling water to raise the mash temp to 170. Is this going to result in any tannin extraction? At that point, I would batch sparge with the remaining sparge water at 170. Is this correct?
 
I appreciate all the responses guys! I'm pretty excited to try and brew soon and see what happens. If I can get a better crush and try a new, seemingly easier sparging technique to improve my efficiency, that would be great. Right now the only thing about brewing that has been bugging me was the low numbers.
 
Khirsah17 said:
I appreciate all the responses guys! I'm pretty excited to try and brew soon and see what happens. If I can get a better crush and try a new, seemingly easier sparging technique to improve my efficiency, that would be great. Right now the only thing about brewing that has been bugging me was the low numbers.
Hey...if it makes you feel better, I'm dialed in at a consistent 72%.

Once you adjust your recipes to a consistent efficiency, you hit your targets right on the nose :D
 
Kaiser said:
ajf,

I don't think that this will provide you much info for batch sparging and for fly sparging. In batch sparging, if your last runnings are above 1.015 then there is nothing you can do about it. Sure you could sparge more, but only to a certain point since you don't want to extend your boil to long. In fly sparging, the gravity of the runnings will not tell you if you had channeling. This you can only determine by adding lots of water, stiring it and taking its gravity. Basically batch sparging the spent grain to summ up the extract that you didn't sparge.

If his problem is the crush, then there is a percentage of the starches that didn't take part in the mash and won't be convered to extract that can be lautered.

Khirsah17,

You never mentioned if you are fly or batch sparging.

Kai
If you end up with a high gravity in the final runnings when batch sparging, then you either have major sparging problems, such as inadequate mixing, low sparge temperature etc, or you are making a very high gravity brew where there just isn't enough sparge water to rinse out the sugars.
I know (from experience) that adjusting the sparge temperature can make a difference of 10% (in my case) in efficiency. Other possibilities are to use a thicker mash leaving more water for sparging, or doing more batches with smaller volumes per batch.
With fly sparging, most of the above also holds true.
In the event that you have channeling, you will probably have an abnormally low gravity at the end of the sparge as you will have extracted the sugars from the "channels" which will be over sparged.
Your suggestion for stirring, and taking a post stir gravity to detect channeling is excellent. (It never occurred to me because I have never had obvious channeling problems.) I shall try it next time I fly sparge, and post the results
 
Kaiser said:
ajf,

I don't think that this will provide you much info for batch sparging and for fly sparging. In batch sparging, if your last runnings are above 1.015 then there is nothing you can do about it. Sure you could sparge more, but only to a certain point since you don't want to extend your boil to long. In fly sparging, the gravity of the runnings will not tell you if you had channeling. This you can only determine by adding lots of water, stiring it and taking its gravity. Basically batch sparging the spent grain to summ up the extract that you didn't sparge.

If his problem is the crush, then there is a percentage of the starches that didn't take part in the mash and won't be convered to extract that can be lautered.

Khirsah17,

You never mentioned if you are fly or batch sparging.

Kai
If you end up with a high gravity in the final runnings when batch sparging, then you either have major sparging problems, such as inadequate mixing, low sparge temperature etc, or you are making a very high gravity brew where there just isn't enough sparge water to rinse out the sugars.
I know (from experience) that adjusting the sparge temperature can make a difference of 10% (in my case) in efficiency. Other possibilities are to use a thicker mash leaving more water for sparging, or doing more batches with smaller volumes per batch.
With fly sparging, most of the above also holds true.
In the event that you have channeling, you will probably have an abnormally low gravity at the end of the sparge as you will have extracted the sugars from the "channels" which will be over sparged.
Your suggestion for stirring, and taking a post stir gravity to detect channeling is excellent. (It never occurred to me because I have never had obvious channeling problems.) I shall try it next time I fly sparge, and post the results

-a.
 
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