Measure Alcohol Concentration for Alcohol Proof by Measuring the Density of Alcohol
Alcohol Concentration Determination Introduction – Pycnometers, hydrometers, and digital density meters are officially recognized methods for the determination / measurement of alcohol proof (ethanol) concentration for quality control and to ensure proper product labeling for declaration of alcohol proof testing for the payment of tax. In the United States, the Alcohol industry is monitored, and tax is collected by the US, TTB. The required standard of measurement of % alcohol within 0.02% accuracy. Thus, very precise measurements are required for proper labeling, tax remittances, and long term record keeping. Having records organized by batch, date, alcohol %, calibration, and temperature control is also of significant importance for an organized Distillery.
Alcohol Proof Measurement – Measure Density of alcohol
Alcohol products are generally labeled with a stated alcohol Proof. This terminology began in the UK; however, in the US, currently the term Proof is determined by multiplying the alcohol % by volume (ABV) X 2. Thus, an alcohol product labeled as 80 Proof is 40% alcohol by volume. An Alcohol product that is 50% ABV would be labeled at 100 Proof.
Measure Alcohol Concentration with a Pycnometer
Pycnometers are not as accurate as other methods. They are very time-consuming and require well-trained laboratory personnel. Results are generally not very reproducible and prone to much human error. Difficulties in alcohol proof testing with a Pycnometer include reading the measurements by eye and holding the temperature at a consistent and accurate level. Using an inexpensive thermometer that is only accurate to +- 0.05° will cause results to be far outside the required accuracy requirements. The need for considerable human judgment with visual readings leaves this method as being far to inconsistent and inaccurate. Typically, measurements will not meet TTB labeling and taxation requirements.
Messung der Alkoholkonzentration - Alkoholtest mit einem Aräometer
Hydrometers are much less accurate than a modern, highly accurate Density Meter or pycnometer. While hydrometers are reasonably easy to use, they require very large sample sizes. Typically, between 300 to 500 ml per measurement is needed. Also, Hydrometers often need off-site calibration. User error is a significant problem with measurements made by eye, and temperature control is also a difficulty. Significant time can be needed to accurately bring and hold samples at temperature and again temperature levels are gauged by the user’s eyes.
An additional issue is of concern with pycnometers and hydrometers, as the alcohol measurement results are difficult to validate and document. Traceability back to sample temperature at the time of measurement and calibration are difficult. The alcohol producer is also only able to keep a manually created log for Temperature, calibration, and % alcohol. This lacks traceability back to a calibrated instrument and electronically recorded temperature reading. While many methods may be acceptable to the US TTB they are of little value if user error causes an inaccurate reading. In a shelf-pull or audit all that matters is accuracy in reporting alcohol by volume. Well organized Distilleries will want an instrument created log of precise temperature, latest calibration, % Alcohol by volume, Proof, batch number, product name, and date. Having these records stored electronically in a modern spreadsheet format greatly aids record keeping.
Alcohol Concentration Measurements for TTB Reporting and Compliance
Für die Berichterstattung und Einhaltung der TTB-Vorschriften ist ein hochpräzises Dichtemessgerät wie das Rudolph DDM 2911 Plus erforderlich. Das Gerät ist von der US TTB zugelassen und wird auch in deren eigenen Labors für Alkoholnachweisprüfungen verwendet. Ein automatisches Dichtemessgerät bietet die einfachste Möglichkeit, die Dichte eines Alkohol-Wasser-Gemisches zu messen. Das Dichtemessgerät wandelt diese Messung dann auch automatisch in eine Alkoholkonzentration und eine Proof-Bestimmung um. Die Messung ist schnell, genau und in hohem Maße reproduzierbar. Nur 1 bis 2 Minuten Zeit und eine Probe von etwa 2 ml sind erforderlich, um eine Genauigkeit von ±0,01 % vol/vol Alkohol zu erzielen. Diese Genauigkeit übertrifft die vom US TTB geforderte Genauigkeit von 0,02 %.
Measuring Alcohol Concentration requires minimal Operator training using the DDM 2911 Plus Density Meter as the most common error of bubbles in the sample has been eliminated. The DDM 2911 Plus Density Meter gives the operator excellent visibility of the entire Oscillating Glass U-Tube to easily detect bubbles, and thus easily avoid inaccurate measurements. Alcohol measurements require very high precision and the presence of even the very smallest of bubbles will alter that precision greatly. However, Rudolph Research Analytical’s exclusive VideoView™ helps the operator load each sample into the density meter without bubbles. The system displays the U-Tube that contains the sample at 2–10× magnification, allowing the operator to see even the smallest bubble. The operator can view the U-Tube while loading the sample then magnify the view up to 10X if needed. In addition the user may use the scanning feature to examine the entire U-Tube before measuring.
Bestimmung des Alkoholgehalts - Verfahren mit dem Dichtemesser
The DDM 2911 Plus is loaded for measurements by injecting a small 1 to 2 ml sample with a syringe. The temperature of this sample will be controlled automatically to within ±0.03 ºC of the required measurement temperature. The DDM 2911 Plus Density Meter will accurately measure the sample’s density. Then automatically perform the calculation from density of alcohol to density of alcohol in water to determine the actual alcohol concentration. This is done by using one or more of the officially recognized alcohol tables; most often OIML, AOAC, or IUPAC. Alcohol concentrations may be determined in the full range of 0 to 100% with a single measurement. Units of concentration may be % vol/vol, %m/m, %wt/wt, or ºProof. The results are displayed on the large 10.4 inch color Touch-Screen and may be saved locally or to any defined location on your network. The results can be sent to any networked printer. You can use it to generate a certificate of analysis with your logo.
Sample identification can be entered manually or with a bar-code scanner or accessory keyboard. Additionally, you can set the DDM 2911 Plus to “Multiple Measurement” mode, which automatically measures the same sample as many times as you choose. The instrument then displays full statistical data for those measurements and lets you print the results or save them to your network.
Einfache Integration mit Ihrer Distillery und Netzwerkspeicher.
Das DDM 2911 Plus arbeitet mit dem Windows™ Embedded-Betriebssystem, das dem Benutzer mehrere Vorteile bietet. Da das Betriebssystem eingebettet ist, ist es unempfindlich gegen Malware oder Viren, da es nicht überschrieben oder verändert werden kann. Die Windows™-Umgebung ist einem PC sehr ähnlich und daher sowohl vertraut als auch einfach zu bedienen. Darüber hinaus kann das DDM 2911 Plus Dateien in einer Vielzahl von gängigen Formaten wie Text, PDF und CSV exportieren. Für Protokolle von Messungen der Alkoholkonzentration sind CSV-Dateien sehr beliebt, da sie direkt in eine EXCEL™-Datei übernommen werden können. Sie werden in den Hauptprotokollen der von einer Brennerei hergestellten Chargen gespeichert.
Für weitere Informationen oder zur Vereinbarung eines Vorführtermins wenden Sie sich bitte an Rudolph Research Analytical, 55 Newburgh Road, Hackettstown, NJ, 07840
P. 973.584.1558 | F. 973.584.5440 | info@rudolphresearch.com | www.rudolphresearch.com
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Messung der Alkoholkonzentration -
Bestimmung des Alkoholgehalts
