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Old 11-27-2012, 11:34 AM   #21
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I would tell the owner of the lhbs about the crush issue and that there were uncrushed grains. There is a lot of conspiracy theory that LHBS guys set their mills to crush poorly on purpose. I don't think that's true because there is sooo much on the Internet about grain crush that the most avid brewers (their largest volume potential customers) are going to know that it's not right and choose to shop elsewhere even paying less to buy on the Internet. There has been no difference in my efficiency between my LHBS's mill and my own except a small drop that I attribute to the LHBS measuring grains a little heavy handed. I have tried setting my mill at a variety of widths going as low at .035 and the only difference when I got that low was a slower sparge. The biggest impact that I have been able to make on my efficiency has been to use an adequate volume of sparge water.

Edit: my efficiency is typically 80% for beers under 5% abv, 75% for 5-6.5% beers and 70% for higher gravity beers. I estimate everything at 75% for simplicity

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Old 11-27-2012, 11:50 AM   #22
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+1 to adequate sparge water. Crush is very important but sparge water can easily be over looked. If you pack your mash tun full and don't leave enough room for sparge water not only will you have low efficiency, but you can even end up with a lower OG when using more grain! For my small batch system I actually have a higher OG with 7 pounds of grain and 1 sparge than I do with 11 pounds!

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Old 11-27-2012, 12:01 PM   #23
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Interesting premise, the idea of stratification. If you drain from a keggle, do you think the sample at the end would be lower gravity because the ball valve pulls from the bottom? I brewed an ipa this weekend and in the end missed target gravity by 9 points. There are a number of other possible mistakes, but this is an interesting thought.

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Old 11-27-2012, 12:29 PM   #24
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I have seen stratification from syrups that aren't properly mixed such as LME and corn syrup, but once it is dissolved is stratification really an issue? Does any one have data showing this, or is it theoretical? I thought that particles will sink (suspensions) but dissolved solids (solutions) will stay pretty homogeneous.

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Old 11-27-2012, 05:43 PM   #25
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Quote:
Originally Posted by WoodlandBrew
I have seen stratification from syrups that aren't properly mixed such as LME and corn syrup, but once it is dissolved is stratification really an issue? Does any one have data showing this, or is it theoretical? I thought that particles will sink (suspensions) but dissolved solids (solutions) will stay pretty homogeneous.
Yes; Personal experience. The higher the gravity brew all grain using fly sparge, in my set up, the lightest gravity run-off goes on top. I have to stir and sample 3-4 times before my gravity stabilizes and it gets higher each Time it's read.
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Old 11-27-2012, 06:07 PM   #26
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Yes; Personal experience. The higher the gravity brew all grain using fly sparge, in my set up, the lightest gravity run-off goes on top. I have to stir and sample 3-4 times before my gravity stabilizes and it gets higher each Time it's read.
I could see an issue in the mash. but I wouldn't call that a solution. When fly sparing it does take some time for the water to trickle through the grain bed. I thought the OP had a problem when taking a sample from the fermentaion vessels.
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Old 11-28-2012, 02:54 PM   #27
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Quote:
Originally Posted by WoodlandBrew

I could see an issue in the mash. but I wouldn't call that a solution. When fly sparing it does take some time for the water to trickle through the grain bed. I thought the OP had a problem when taking a sample from the fermentaion vessels.
Yes, he did. He said he topped the fermentor to hit a target volume with water. My thought is that the OP's innitial gravity reading was not representative of the mean of the gravity of the wort plus the added water due to it not being homogenous at the time he sampled it. Furthermore, with the gravity of water being 1.000, if he obtained the sample from the top, the OG number he got would have been low, which is what he said he saw.
It's the same principle if you bottle and don't stir the priming sugar solution into the full bucket. There are those that do this, but, at some point it usually ends in inconsistent carbing for the same reason I mentioned above.

It is my experience that it actually takes a conscious effort to get the high gravity and low gravity solutions to mix. You can't just pour it in and expect them to mix - same as in fly sparge when trying to get an accurate kettle full gravity.
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Old 11-28-2012, 03:53 PM   #28
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The best example I can think of showing stratification of solutions is a trying to pour a back and tan... without a spoon. Even with a spoon it is difficult achive something other than just brown.

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Old 11-28-2012, 05:33 PM   #29
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Quote:
Originally Posted by WoodlandBrew
The best example I can think of showing stratification of solutions is a trying to pour a back and tan... without a spoon. Even with a spoon it is difficult achive something other than just brown.
The difference in gravity of two finished beers is exponentially closer than that of unfermented wort and water.
The example I think that closer fits is that of grenadine in a tequila sunrise....

In fact; let me test that out
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Old 11-28-2012, 05:42 PM   #30
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Btw... I'm really not saying your wrong; you defiantly have a good point - I'm just trying to explain my POV. My example is a little more exaggerated in the opposite direction than yours. My stratification issues have gotten me before. Your process is different and therefore your experiance will be different.

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