Digital Density Meters - recommendations please

[Monopol Spirits Distillery]

Looking to purchase digital density meter, does anybody have any recommendations, model numbers, pricing?

Thank you

[bluestar]

18 hours ago, Monopol Spirits Distillery said:

Looking to purchase digital density meter, does anybody have any recommendations, model numbers, pricing?

Thank you

Can't properly answer the question unless we know what you plan to use it for. Is this for final proof determination at bottling, and thus requiring full TTB accuracy? Or just something for quick measurements during production?

[Monopol Spirits Distillery]

Honestly, I'd like to find out about both options.

Thank you for your response.

[Eud]

They're usually expensive, and only a few are approved for proofing by the TTB.

Not sure if this list is current, but it was updated in 2017.

https://www.ttb.gov/pdf/2014-7-21-device-approval-guidlines.pdf

Someone here was selling an Anton Parr back in March.  

[Monopol Spirits Distillery]

What about the second option, without TTB approval. My final product is blended with honey and juice so density meter will not work. But I definitely need reliable device to check proofing during distilling process.

[Julius]

52 minutes ago, Monopol Spirits Distillery said:

What about the second option, without TTB approval. My final product is blended with honey and juice so density meter will not work. But I definitely need reliable device to check proofing during distilling process.

For high solid liquids you must do benchtop distillation to determine proof without an approved unit. TTB has video walkthrough of the process.

 

if you have the money, a DMA with an alcolyzer will save you sooooo much time in the long run (for a price).

[Monopol Spirits Distillery]

What would you recommend for day to day operation to check proofing, which electronic density meter is reliable?

[bluestar]

18 minutes ago, Monopol Spirits Distillery said:

What would you recommend for day to day operation to check proofing, which electronic density meter is reliable?

The EasyDens is the cheapest thing you can get: https://www.anton-paar.com/us-en/products/details/density-and-concentration-meter-easydens/

But more convenient and accurate is the Snap 40: https://shop.anton-paar.com/us-en/snap-41.html

None of these are anywhere near accurate enough to make the final TTB-required bottling proof measurement.

And as mentioned before, you are going to have to use the distillation method to determine proof of your final product most likely, and you will need accurate measures of temperature and volume to do that.

[Silk City Distillers]

I feel like there is enough drift on the handheld Anton Paar units that you need to recalibrate with distilled water every day.

Wondering if anyone else has had the same experience.  We use the DMA35 for quick, intermediate measurements, and we use Alcodens for all proofing/dilution calculations.  More than once I've gone through proofing (which may extend more  than a day) with Alcodens only to realize the DMA35 was off by a few tenths.  Alcodens calcs are always laser precise, the density meter, not so much.  Nearly every time when the measured proof had a deviation from the calc, it's just that the meter was off.

Glass rules.

If you are working with sugar additions (honey),  start honing your lab skills, a digital density meter is not going to save you any material amount of time.

[Skaalvenn]

3 hours ago, Silk City Distillers said:

I feel like there is enough drift on the handheld Anton Paar units that you need to recalibrate with distilled water every day.

Wondering if anyone else has had the same experience.  We use the DMA35 for quick, intermediate measurements, and we use Alcodens for all proofing/dilution calculations.  More than once I've gone through proofing (which may extend more  than a day) with Alcodens only to realize the DMA35 was off by a few tenths.  Alcodens calcs are always laser precise, the density meter, not so much.  Nearly every time when the measured proof had a deviation from the calc, it's just that the meter was off.

Glass rules.

If you are working with sugar additions (honey),  start honing your lab skills, a digital density meter is not going to save you any material amount of time.

We have had a Snap51 for the past year and it's always accurate and repeatable. We do not use it for fermentation, low wines or anything where it could become coated/contaminated/etc.

When we bought it we also purchased 3 vodka bottles from 3 different big producers.  We recorded the indicated proof on the bottle itself.  We use those to test it's calibration (along with following the owners manual) and have not noticed any inaccuracy beyond a couple hundredth of a proof.  We also receive GNS from a supplier who has a full lab, and our test is always inline with their readings (again, within 1-3 hundredths).

We do use certified and calibrated glass hydrometers per the regulations, and it's laughable to think that they are TTB certified and a very precise digital meter is not. Maybe someday we'll be able to throw those antiques into the junk drawer...

[Patio29Dadio]

We have a new DMA35 with the glass meter and it seems to be spot on within its tolerances.  We use it for everything... density, proof, brix.  After every use we pull in several pumps of RO water to clean out the glass senor/meter.   We use it for production and then switch to certified hydrometers and thermometers in a graduated cylinder for proofing before bottling.   Frankly, I cannot justify the price of the bench-top Anton Paar density meter and alcoizer.    And I like the proofing process with the certified glass pieces and the TTB proofing tables.   I trust my hands and eyes more than I do a complex and expensive machine. 

[bluestar]

22 hours ago, Silk City Distillers said:

I feel like there is enough drift on the handheld Anton Paar units that you need to recalibrate with distilled water every day.

Wondering if anyone else has had the same experience.  We use the DMA35 for quick, intermediate measurements, and we use Alcodens for all proofing/dilution calculations.  More than once I've gone through proofing (which may extend more  than a day) with Alcodens only to realize the DMA35 was off by a few tenths.  Alcodens calcs are always laser precise, the density meter, not so much.  Nearly every time when the measured proof had a deviation from the calc, it's just that the meter was off.

Glass rules.

If you are working with sugar additions (honey),  start honing your lab skills, a digital density meter is not going to save you any material amount of time.

They drift, they are sensitive to temperature equilibration time, so work better if you are near the nominal measurement temperature. DMA35 (or Snap 40, 50) are NOT accurate enough to meet TTB requirements for measuring proof to +0/-0.3 as per the CFR. Even the high end units need periodic calibration, and are sensitive, for example, to changes in air pressure...

[bluestar]

18 hours ago, Skaalvenn said:

We have had a Snap51 for the past year and it's always accurate and repeatable. We do not use it for fermentation, low wines or anything where it could become coated/contaminated/etc.

When we bought it we also purchased 3 vodka bottles from 3 different big producers.  We recorded the indicated proof on the bottle itself.  We use those to test it's calibration (along with following the owners manual) and have not noticed any inaccuracy beyond a couple hundredth of a proof.  We also receive GNS from a supplier who has a full lab, and our test is always inline with their readings (again, within 1-3 hundredths).

We do use certified and calibrated glass hydrometers per the regulations, and it's laughable to think that they are TTB certified and a very precise digital meter is not. Maybe someday we'll be able to throw those antiques into the junk drawer...

Actually, it is not as laughable as you think. If you actually used the precision and calibrated glass hydrometers correctly, as described by TTB gauging manual, a skilled user will meet the requirements. But most people just don't have the necessary skill or patience. On the other hand, the Snap 51 can NOT meet requirement. Even if you checked a Snap 51 against something more accurate, and you found it was accurate enough, that would be accidental, and no way to assure it would not drift out of accuracy. While that digital meter may seem to have enough PRECISION, it does not have the required ACCURACY.

[bluestar]

17 hours ago, Patio29Dadio said:

We have a new DMA35 with the glass meter and it seems to be spot on within its tolerances.  We use it for everything... density, proof, brix.  After every use we pull in several pumps of RO water to clean out the glass senor/meter.   We use it for production and then switch to certified hydrometers and thermometers in a graduated cylinder for proofing before bottling.   Frankly, I cannot justify the price of the bench-top Anton Paar density meter and alcoizer.    And I like the proofing process with the certified glass pieces and the TTB proofing tables.   I trust my hands and eyes more than I do a complex and expensive machine. 

I agree the DMA35 (and SNAP equivalents) are good working digital hydrometers. But now that we have a precision unit that meets the TTB requirements, and have been able to see how our DMA35 and SNAP40 perform with respect to it, we know from experience they are not a substitute for the higher accuracy instrumentation required by the TTB.

[Skaalvenn]

57 minutes ago, bluestar said:

Actually, it is not as laughable as you think. If you actually used the precision and calibrated glass hydrometers correctly, as described by TTB gauging manual, a skilled user will meet the requirements. But most people just don't have the necessary skill or patience. On the other hand, the Snap 51 can NOT meet requirement. Even if you checked a Snap 51 against something more accurate, and you found it was accurate enough, that would be accidental, and no way to assure it would not drift out of accuracy. While that digital meter may seem to have enough PRECISION, it does not have the required ACCURACY.

I guess I have no idea what I'm doing then. /s

[bluestar]

On 8/1/2019 at 10:35 AM, Skaalvenn said:

I guess I have no idea what I'm doing then. /s

Not sure what your point is here @Skaalvenn, or if you are just being humorous? Really, if you use the glass hydrometers per the gauging manual, you can get to the required accuracy, but it is slow and requires precise lab methods, like measuring temperatures after full equilibration of equipment to 0.1 deg C accuracy. Many people purchase the regulation calibrated hydrometers for $250 or so, but don't invest the even greater amount required for a precision calibrated thermometer or a temperature controlled bath, and so can not meet the TTB requirement. And setting up the baths for temperature equilibrium, etc., means (at least for me) that a single measurement can easily take a half hour (remember, you have to repeat the measurement at least 3 times to get the required statistical averaging). Hence, why we eventually purchased one of the approved digital densitometers, and now know for sure that the Snap is not accurate enough.

[Skaalvenn]

2 hours ago, bluestar said:

Not sure what your point is here @Skaalvenn, or if you are just being humorous? Really, if you use the glass hydrometers per the gauging manual, you can get to the required accuracy, but it is slow and requires precise lab methods, like measuring temperatures after full equilibration of equipment to 0.1 deg C accuracy. Many people purchase the regulation calibrated hydrometers for $250 or so, but don't invest the even greater amount required for a precision calibrated thermometer or a temperature controlled bath, and so can not meet the TTB requirement. And setting up the baths for temperature equilibrium, etc., means (at least for me) that a single measurement can easily take a half hour (remember, you have to repeat the measurement at least 3 times to get the required statistical averaging). Hence, why we eventually purchased one of the approved digital densitometers, and now know for sure that the Snap is not accurate enough.

My point was that I know how to proof spirits, I know the procedures, I know what the equipment costs, and that it takes a long time to do correctly.  It's not rocket science, it's the elementary (and required) part of our industry that we should all know how to do, and do very well.

I'm also saying, that I test it against my Snap51 multiple times per week, I test it against known samples, and my Snap51 is always dead on.  Would I trust it if I were proofed to 79.99 proof on an 80.00 proof label? Absolutely not, would I trust it saying 79.90 proof on an 80 proof label? Absolutely.

[bluestar]

20 hours ago, Skaalvenn said:

My point was that I know how to proof spirits, I know the procedures, I know what the equipment costs, and that it takes a long time to do correctly.  It's not rocket science, it's the elementary (and required) part of our industry that we should all know how to do, and do very well.

I'm also saying, that I test it against my Snap51 multiple times per week, I test it against known samples, and my Snap51 is always dead on.  Would I trust it if I were proofed to 79.99 proof on an 80.00 proof label? Absolutely not, would I trust it saying 79.90 proof on an 80 proof label? Absolutely.

First, just to be clear, I agreed with your point that it is tedious. BUT, while it may not be rocket science, it IS chemical lab technique, which I assure you some small distillers don't understand or have much experience with, even if you and I do. Sometimes my answers here are meant as much for the other possible readers of the thread as they are to the person I may be responding to. So I do agree that "we should all know how to do, and do very well", my specific point, but that many do not.

But I also DISAGREE with your second point. The SNAP51 can not meet the TTB requirements, and I don't know how you would know it is "dead on" unless you are regularly testing it against a unit that is 10x more accurate or better. Anton Paar rates the accuracy to 0.1% ABV, or 0.2 deg proof, even though it reads out to the 0.01 digit. That is not accurate enough to measure proof to better than +0, -0.3 since your range on an individual reading would be +/- 0.2, which is more than is allowed legally. If the SNAP51 had twice the accuracy of 0.05%ABV or 0.1 deg proof, you could possibly claim you are in the range if you had a spot on reading of -0.15 proof, for example. But not really. The -0.3 proof under measurement allowed by the TTB is NOT intended as providing an accuracy range for your measurement. It was intended to allow some loss in %ABV during bottling, so that if you measured close to perfect from your bottling tank, you would end up within the range after being in the bottle (not obvious to find in the CFR, but explained at length to me by a visiting TTB officer during our inspection, see section 5.37 (2) (b) (3) ). Hence, the expectation that you will measure more accurately than +0, -0.3 proof to allow a drop within that range. The guideline is that you should be able to measure 0.02 proof accurate (after averaging, for glass you read to 0.05), so that is 0.01% ABV accurate or better.

Here is an example of how you can (and TTB says some do) run into trouble using something like a SNAP51. You measure something as 100.0 proof (readout may be 100.00, but only accurate to tenths). Since your accuracy is 0.2 proof, that could actually be 100.2 proof, and that would be illegal if tested at that proof in the bottle.

[bluestar]

21 hours ago, Skaalvenn said:

...would I trust it saying 79.90 proof on an 80 proof label? Absolutely.

But you shouldn't. It is only accurate to +/- 0.2 proof.

[Skaalvenn]

*sigh*

I'll just quote myself here.

On 7/31/2019 at 2:45 PM, Skaalvenn said:

When we bought it we also purchased 3 vodka bottles from 3 different big producers.  We recorded the indicated proof on the bottle itself.  We use those to test it's calibration (along with following the owners manual) and have not noticed any inaccuracy beyond a couple hundredth of a proof.  We also receive GNS from a supplier who has a full lab, and our test is always inline with their readings (again, within 1-3 hundredths).

We do use certified and calibrated glass hydrometers per the regulations, and it's laughable to think that they are TTB certified and a very precise digital meter is not. Maybe someday we'll be able to throw those antiques into the junk drawer...

I will agree with you that some people don't understand how to properly proof a spirit, heck, I've taken calls from distillers having trouble mashing and and find out they don't even own a thermometer...

[bluestar]

On 8/3/2019 at 1:27 PM, Skaalvenn said:

*sigh*

I'll just quote myself here.

I will agree with you that some people don't understand how to properly proof a spirit, heck, I've taken calls from distillers having trouble mashing and and find out they don't even own a thermometer...

I am not sure what we are debating, now. I know I was not saying you were not properly using the analog methods to make a measurement. Is what you are saying is that you are checking the SNAP 51 by using the analog methods, and that is how you are regularly verifying that it is as accurate as those measurements? Okay, if I assume that was what you meant, my point earlier is that it remains only coincidence, that your unit so checked happened to repeatedly do so, because as the unit is designed and built, the manufacturer does not and can not assure that the accuracy is any better than +/- 0.2 degree proof, which means you can not extrapolate from even 1000 measurements to that point and assume going forward the instrument is measuring correctly thereafter. Even if your particular meter, by some act of the gods, happens to just manage to do so, there is no reason to assume another SNAP 51 will do so, or that yours may not suddenly stop behaving that way.

[Skaalvenn]

21 minutes ago, bluestar said:

I am not sure what we are debating, now.

I'm not entirely sure either.

We use the Snap to get us to bottling proof, as its far faster. We then verify it's reading is accurate by approved TTB methods and equipment, and proceed to bottle. We have not seen any sway in the reading from the Snap.   What's your issue with this?

[bluestar]

On 8/6/2019 at 10:20 AM, Skaalvenn said:

I'm not entirely sure either.

We use the Snap to get us to bottling proof, as its far faster. We then verify it's reading is accurate by approved TTB methods and equipment, and proceed to bottle. We have not seen any sway in the reading from the Snap.   What's your issue with this?

Again, I am not criticizing how you are measuring your proof. As you said, you are using the approved TTB methods and equipment. Great! But you were implying, I interpreted, that the SNAP 51 COULD be used to meet this requirement, if only the TTB would allow it. That is my issue. It is not true. Regardless as to your specific experience that every time you have ever used the SNAP 51 at the same time that you used the TTB methods that you got exactly the same result to the hundredths, it is not good evidence that anyone else, or even you for that matter, could successfully replace the TTB methods with use of the SNAP 51 for final proofing. I am taking all this effort to answer your comments because I don't want anyone else reading the thread to come away with the mistaken impression that the SNAP 51 is accurate enough to make the required measurement, even if you are not using it for that purpose! Remember, the thread was started by a newbie asking for recommendations on digital densitometers.

[Dsking416]

Well, that escalated quickly...

[Longleaf Distilling]

Sorry to drum up an old topic, but since the Label Modernization Act changed the alcohol tolerance to +-0.3%, doesn't than mean that devices like the SNAP-41 are compliant now? Where is the list of approved devices? I haven't been able to find that anywhere.