One of the interesting facts I found out at the ADI conference was that whiskey has enough dissolved solids to throw off your proof readings. I guess it should have been obvious just looking at whiskey.
We just sent our stuff off to a lab to have the proof solids and the proof obscuration values checked. We were off more than I thought we would be. We are a bit lucky to have a DMA 5000, but with the amount of solids, it's off too much to be accurate.
Many people I know in the industry aren't properly proofing their whiskey. Hopefully, this will prevent someone from being fined or "dinged" by the TTB. I know we will get compliant from here on.
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How will you get compliant ?
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I would be interested to know what percentage of variation you are finding between the DMA 5000 results, and results from the lab.
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I would be interested to know what percentage of variation you are finding between the DMA 5000 results, and results from the lab.
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I can't confirm this, but I would expect the older a whiskey is the more obscuration... more extraction = more solids to obscure true proof. Our whiskey was sent to the TTB lab who found obscuration was .4 degrees of proof- enough to put it outside gauging spec. Our Whiskey is 4.5-5 years old.
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Guy, we did find that older whiskey had more obscuration than younger whiskey, at least in our findings.
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John D, to measure ABV accurately you need to get rid of anything other than water and ethanol in the sample. This is often done with a "proofing still", a small glass still that is used to boil off all the liquid and leave behind the solids that "obscured" the density reading. You can find the detail in TTB regs somewhere.
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For those interested, here are my results:
2 year bourbon (92 proof product)
DMA5000 (ours) proof: 91.82
DMA5000 (lab) proof: 91.64
Obscuration (lab): .488
True Proof: 92.13 (Their DMA + obscuration)
7 year bourbon (99 proof product)
DMA5000 (ours) proof: 98.689 (last bottle off line)
DMA5000 (lab) proof: 98.52
Obscuration (lab): .792
True Proof: 99.31 (Their DMA + obscuration)
7 year rye (99 proof product)
DMA5000 (ours) proof: 98.634 (last bottle off line)
DMA5000 (lab) proof: 98.42
Obscuration (lab): .599
True Proof: 99.02 (Their DMA + obscuration)
You can see that just according to my DMA, with no obscuration, I was still a bit off on final proof.... .011 on our 7 year bourbon and .066 on our 7 year rye. I'm shocked that we were that far off given our level of care that we give to proofing.
I was even more shocked to see the difference between their DMA 5000 and ours, .16 to .21 between the two instruments.
Given this level of obscuration, are we allowed .3 proof of error (on the low side only) or .5 proof of error? I'm not sure about that.
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For those interested, here are my results:
2 year bourbon (92 proof product)
DMA5000 (ours) proof: 91.82
DMA5000 (lab) proof: 91.64
Obscuration (lab): .488
True Proof: 92.13 (Their DMA + obscuration)
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I was even more shocked to see the difference between their DMA 5000 and ours, .16 to .21 between the two instruments.
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