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Old 11-25-2012, 03:22 PM   #11
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This was our first all grain brew, however we know what we're doing. The wort appeared to be packed full of sugars. Original gravity calculation was 1.102. Since this was the first time brewing this recipe, we were unsure of several factors such as how much water the grain would take on so we fell a little short of the estimated final volume and did fill. We're thinking maybe that late addition water could have affected the reading. Also, I took a sample from the top and tested that. Perhaps it was a problem with the wort from the top.

I don't know how you figure it appeared to be packed with sugars, but anyways..

So you came up short on volume, that should have given you a higher OG. But then you topped up with water.. did you do it at the end of the boil? You'll obviously want to not do that all the time, so figure out the calculation to get your volume.

If you added water, you probably didn't mix it well. Stratification will occur with the higher gravity sinking to the bottom. Chance are, you got the top end with the water. It's pretty hard to get it all mixed in really well to get a reading.
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Old 11-25-2012, 03:47 PM   #12
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Mash volume and grain absorption would be useful to know here as well.

If the mash volume was 7.6 gallons, and the grain absorption was 0.2 gallons per pound that would be 3.8 gallons absorbed. If the OP did not sparge that would explain the problem.

If the mash volume was 5 gallons with a single batch sparge I bet the result would also be about where the OP ended up.

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Old 11-25-2012, 08:32 PM   #13
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I figured it was packed w sugars because the entire boil was basically a hot break. We did top off w water so I figure that is the problem. We did mash and did one batch sparge. Being as it was our first time I was unsure exactly what to expect w grab absorption...I had predicted 2.5 gsll

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Old 11-25-2012, 08:54 PM   #14
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Mash volume and grain absorption would be useful to know here as well.

If the mash volume was 7.6 gallons, and the grain absorption was 0.2 gallons per pound that would be 3.8 gallons absorbed. If the OP did not sparge that would explain the problem.

If the mash volume was 5 gallons with a single batch sparge I bet the result would also be about where the OP ended up.
If he didn't sparge, he'd have a higher gravity, due to the lower volume. Opposite of his problem. He added water to get his volume, and probably added too much, and didn't mix top up water well enough for taking a hydro sample..

Just my guess.
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Old 11-25-2012, 10:25 PM   #15
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Yes, the wort would have high gravity in the boil, but after topping off it would be low, which is what he reported.

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Old 11-26-2012, 12:42 AM   #16
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Quote:
Originally Posted by citylights
I figured it was packed w sugars because the entire boil was basically a hot break. We did top off w water so I figure that is the problem. We did mash and did one batch sparge. Being as it was our first time I was unsure exactly what to expect w grab absorption...I had predicted 2.5 gsll
It is a lot harder to mix water and high gravity wort together than many people give credit. Without a concerted effort to mix the wort/water, I would expect that the gravity reading you got was falsely low.

No way to know now unless you know someone with a SCABA or maybe one of those new lab test kits out there.

Do another brew and see if you get the same result.
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Old 11-26-2012, 02:58 AM   #17
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Best advice I can add is take more gravity readings. Minimum take a preboil gravity. I batch sparge and take a gravity reading on each set of runnings. With this size grain bill I likely would have had 2 sparge infusions, so I would have taken readings on the first runnings, 2nd, and 3rd, then a preboil and finally an o.g. After cooling.

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Old 11-26-2012, 01:29 PM   #18
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Thanks everyone. You pretty much confirmed what I thought had happened...just wanted some other opinions....it's now in the fermenter rapidly fermenting

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Old 11-26-2012, 01:38 PM   #19
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Thanks everyone. You pretty much confirmed what I thought had happened...just wanted some other opinions....it's now in the fermenter rapidly fermenting
At what temperature? You'll want to keep this one near the low end of the yeast's preferred range as it has a lot of sugars and the yeast tend to get too excited with all that food and like to make some byproducts that aren't particularly beneficial to the flavor of your beer. Once the fermentation settles down it will be OK to let it get warmer.
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Old 11-26-2012, 03:16 PM   #20
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I'm sure others here have targeted your issues more than I would, but I can't stress enough a good crush. I have a local HBS that even brews their own beers in house, for sampling, so I figured their crusher would be fine to use. I switched to all grain 3 batches ago and the first two were about 10 points lower than they should have been on OG post boil, and about 15 points low on pre-boil. I changed things up on my end on the second brew, made sure to hit water exact, figured my boil off rate exactly. The last thing was the crush. I ddin't pay much attention originally, because as I said, they brew in house and use that mill, so why would it be off. On closer inspection though, over half the grain was still completely intact grain. I sprung for my own mill before this last batch and went from roughly 56% efficiency up to 74% by using my own crusher.

Being new to the all-grain business, I'm sure that the lowe effieciency was in part to my mistakes and getting a system down, but a little experience, combined with the look of the grain after my home crush compared to the HBS, was night and day.

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