Technology - Method comparison to measure alcohol concentration
Method comparison to measure alcohol concentration
Cleanness
Meas. of flow Initial Running
Usability Accuracy Calibration Time Channel Cost Cost
Hydrometer Difficult Low Difficult Long Moderate Low Low
Infrared method Difficult Middle Difficult Short Required High Low
Gas
chromatography Difficult Middle Difficult Long Required High High
Distillation
plus alcohol meter Easy Good Easy Short Moderate Middle Low
Hydrometer
The price on the market is reasonable, however, cost of annual calibration at third party is expensive. Operator has to take care of the operation since it is made of glassware. When this method is used, large volume of sample needs to be prepared whilst operator has to wait until temperature reaches the specific testing temperature. The human error depending on operator's experience is large, so it is very difficult to get reliable results everyday.
Infrared Method
Gas chromatography
This method is the latest technology. However, the price is still not reasonable for general alcoholic manufacturers and some countries don't approve it as an official method. This method has gap of accuracy between test result and theoretical value when alcohol concentration is high. Since operators needs to prepare calibration standard, it is not easy works for unexperienced operators.
This method is efficient when you prefer to get several elements results from one sample. However, operator has to prepare carrier gas and do calibration with standard solutions and the initial cost is expensive. The operation is also not easy for general operators in alcoholic manufactures.
Distillation plus Alcohol Meter
This is a traditional method and the result is most reliable. In many countries, this process is adopted to method of national regulation. Before measurement of alcohol concentration by alcohol meter (density meter), the process of distillation where the organic substance like sugar is removed from the sample solution. After distillation the mixed solvent (only pure water and alcohol) is tested by alcohol meter. The biggest advantages of alcohol meter ALM-155 is the ability to measure any colored sample and process high viscous sample.