Measuring Alcohol Content in Wine for TTB BATF label approval and taxation
What is a Dujardin-Salleron, Alcohol Burner Ebulliometer? Sounds like a serious human viral disease – no wait – that’s Ebola (or hemorrhagic fever).
Per the US Tax and Trade Bureau (TTB formerly BATF or Bureau of Alcohol Tobacco and Firearms – a much cooler sounding name) wines over 14% must be accurately labeled +/- 1%, Wines 14% or less can be labeled “table wine” or or must be +/- 1.5% in alcohol percent.
Eagles Nest uses the aforementioned device developed circa 1870, it is TTB/BATF approved and popular throughout the wine making world. The Dujardin – Salleron Ebulliometer is a good combination of simplicity and accuracy for the testing the alcoholic content of dry wines.
A ebulliometer is a measuring device that is designed to evaluate the boiling point of different types of liquids. It’s use in the wine industry is based on the fact that alcohol boils at (78.4°C) a lower temperature than water, so the boiling point of alcohol-water mixtures changes as a function of their concentration.
A precision thermometer is involved, to determine the boiling temperature of the wine within 0.02°C. The boiling point of any liquid depends on the atmospheric pressure, so the zero point has to be set against the boiling point of pure water prior to starting each test.
The method is fairly quick and sufficiently accurate (+-0.5 %vol) for general purposes.
It is affected by atmospheric pressure changes, a barometric change of 4 mm (during a test) would cause an error of 0.5 %vol. A simple ebulliometer is less accurate than the Distillation method.
An ebulliometer will provide one of the easiest methods of determining the alcohol content in wine. The test is based on the difference in boiling points of water and wine, and the ebulliometer provides a very accurate measure of these factors. Distillation methods are slightly more accurate, but require more time. The ebulliometer will not give an accurate reading for wines with high residual sugar levels, and these wines must first be distilled or diluted with water and the result factored. The US Treasury Dept officially approves the Dujardin-Salleron ebulliometer for use in commerce.
The Dujardin-Salleron ebulliometer design dates from 1855
Some wine instrumentation history
In the Book of Genesis, the Bible presents the first wine-grower on Earth : Noah.
Beginning in 500 B.C., Greeks and Romans spoke of wine and the grape vine in their writings. They even attributed a specific god to them; Dionysus for the Greeks, Bacchus for the Romans.
Egyptians and Arabs also knew wine and were the first to talk about “alcohol”, which is one of the essential elements in wine. Many engravings, dating from this period, depict archaic stills.
The first alcoholometer appeared during the Roman times. Wine, vineyards and measuring instruments have been known for centuries.
During the eighteenth and nineteenth centuries, the evolution of knowledge about wine and wine-making took on a new dimension. Chemists (pharmacists or physicians) such as Antoine Baumé (1728-1804) and Joseph, Louis Gay-Lussac (1778-1850) put together the basis of the first biochemical formulas by stating that sugar is converted into alcohol and carbon dioxide.
Louis Pasteur (1822-1895) was the first to demonstrate that fermentation is due to microorganisms.
Jules Salleron (1829-1897) created a company specialised in precision instrumentation in 1855. Salleron invented his first still, the acetimeter followed by his reknown ebulliometer still used today. Around 1880, Jules Dujardin (1857-1947) joined the company. Dujardin author of many leaflets and research papers, he took over in 1889 and associated his name to that of Salleron to form the Dujardin-Salleron Establishments. In 1987 the name of the company was changed to Les Laboratoires Dujardin-Salleron.
