Did you know that alcohol has a lower boiling point than water?
Alcohol in wine is derived from the natural grape sugars and any sugar enrichment. There have been several methods of measuring the alcohol content of a liquid, and all require a representative, homogeneous sample. The principal methods have included the use of a hydrometer, a refractometer, a chromatograph, the spectroscopy, or an ebulliometer.
For decades, winemakers have used an ebulliometer to determine the alcohol content of wine using the boiling point method measured by this tool to monitor fermentation, verified the “correct” alcohol content before bottling, and obtained “reliable” results.
The Wine History Project contains a remarkable example of the ebulliometer in our collection. The first one was used successfully in France in 1838. Many scientists worked to perfect it.
The history of the ebulliometer is fascinating because over 188 years, the instrument continues to be a cornerstone in testing wine for alcohol content. It plays an essential role in the food industry. Here is the story as it unfolds in France.
The Ebulliometer Was First Known As The Ebullioscope
The name ebulliometer has its roots in the Latin word “ebullio” meaning to boil or bubble up. The principle of ebulliometry is that alcoholic solutions have a lower boiling point than water. A winemaker will first heat a sample of water and observe the boiling point, then repeat the test with a sample of wine. As a note: the higher the alcoholic content of the wine, the lower the boiling point will be.
In General
In physics, an ebullioscope, from Latin ebullire “to boil”, is an instrument for measuring the boiling point of a liquid. This tool is used for determining the alcoholic strength of a mixture. The process is known as ebullioscopy. When an alcoholic liquid is heated, its boiling point drops depending on how much alcohol is present.
It allows the user to determine the alcohol content of wine using the boiling point method, ensuring quick and accurate readings for optimal fermentation control. The ebulliometer has been an essential tool for winemakers. Its use of heat-resistant glass was necessary in the design of the tool.
The advantage of utilizing the ebulliometer method is that data can be determined more quickly, degassing is not required, and simple apparatus and straightforward procedures are used. Winemakers use an ebulliometer, which determines the alcohol content of wine using the boiling point method measured by this tool to monitor fermentation, verify the correct alcohol content before bottling, and obtain reliable results.
According to some writings, the main drawback to ebulliometry is that it is time-consuming and sensitive to changes in atmospheric pressure. And sweet wines should be distilled and brought back up to volume prior to ebulliometry, which adds an extra step.
However, the boiling point of any liquid depends on the atmospheric pressure, so the zero point must be set against the boiling point of water prior to starting each test.
Boiling point of alcohol: 78.4 degrees Celsius / 173.12 degrees Fahrenheit
Boiling point of pure water: 100 degrees Celsius / 212 degrees Fahrenheit
Original Patent For Ebullioscope
The first ebullioscope, which was used for measuring alcoholic content, was invented by Abbé Brossard-Vidal in 1838. The advantage of this Brossard-Vidal invention was that the boiling point known as relatively insensitive to other components such as sugars was mentioned. The French patent was filed November 23, 1844, and the French patent was issued June 18, 1845. While historical records from 1845 mention reports and updates on his instrument by the Societe d’encouragement pour l’industrie nationale, patent logs of that exact date reflect contemporaneous land grants or colonial filings rather than foundation ebullioscope patent.
Brossard-Vidal (… -ca.1863)
A professor in Toulon, France, which is located on the Mediterranean coast in rugged limestone mountains, patented an ebulliometer called the centesimal oenoscope. It underwent various modifications and improvements and was presented to the Academy of Sciences in 1848. Upon Abbot Vidal’s death in 1863, Vidal’s sister, Mademoiselle Marie Euphresine Elisabeth Brossard-Vidal, inherited the invention from her brother, but was unsuccessful. She fell into poverty. (see Malligand)
Simplified Definition: The boiling point of a substance is the temperature at which the vapor pressure of a liquid equals the pressure surrounding the liquid and the liquid changes into a vapor.
Pierre Marie Edourd Malligand of Paris, France, was given U.S. Patent No. 173,128, which was officially patented on February 8, 1876, after the application had been filed on July 6, 1875. This device, still used by winemakers, measures the alcohol content of wines, using the “Malligand degree” (Mo) as a unit of measure.
Malligand claimed that “instead of directly heating the bulk of the liquid, a circulation of the liquid is produced in a tube exterior of the boiler.” He also claimed that “the instrument may be used for determining the boiling points of liquids generally, either alcoholic or not, and whether simple or compound, the thermometer being immersed in the liquid contained in the boiler, or merely in the steam of said liquids”.
Pierre Marie Edouard Malligand (?.-ca. 1900)
A wealthy wine merchant and owner of the firm E. Malligand Fils, based in Paris in the 1870s at 1 Boulevard S. Michel, likely a friend of Vidal, in addition to supporting his friend’s sister, took an interest in perfecting the abbot’s device to provide his sister with a source of income. To do this, he brought together a physicist, a scientific apparatus manufacturer, and glassblowers and thermometer makers. Pierre Malligand was a French engineer who developed this instrument through the use of tests and improvements which continued for about twelve years, and in 1874, Malligand presented a well-functioning ebulliometer to the Academy of Sciences, which gave it extremely positive feedback. The ebulliometer, simply called the “Malligand” after the project’s sponsor, quickly became a success, spreading to all wine-producing countries.
The instrument consists primarily of a graduated glass bulb connected to a thermometer and a glass container containing the sample to be analyzed. The liquid is placed in the ebulliometer’s glass bulb. The liquid is then heated until it begins to boil. During the boiling, the thermometer records the temperature at which this process occurs.
Since the presence of alcohol in the solution increases its boiling point compared to pure water, by comparing the boiling temperatures of the analyzed solution and the water, it is possible to calculate the percentage of alcohol present in the liquid.
This is the original drawing of the Malligand ebullioscope in the patent.
This is a schematic drawing.
Francois-Marie Raoult, a French chemist, built a later version, which had difficulty determining the exact temperature. In 1887, Ernst Otto Beckmann invented something to overcome that difficulty with the Beckmann thermometer. This improvement made the ebullioscope a standard apparatus to determine the molecular weight of substances in solution by using ebullioscopic constant of the solvent.
Ernst Otto Beckmann (7/4/1853 – 7/12/1923)
Beckman was born in Solingen, Germany. His research included topics spanning pharmaceutical, organic, inorganic, analytical, physical, food, and applied chemistry. One of the things he is best known for is his invention of the differential thermometer. The thermometer is named for him. This added to the ebullioscope made for an improved apparatus. The accuracy of the instrument is high. The instrument can measure temperature differences at either higher or lower temperatures.
The WHP Dujardin-Salleron Ebulliometer – Photos by Cindy Lambert
Dujardin-Salleron Ebulliometer
This is the Ebulliometer which is part of the Wine History Project of San Luis Obispo County Collection. It is stored in a wood box with partitions creating spaces for the various parts that make up the apparatus. The artifact was located and purchased from the California Wine Museum, operated by Jim McCormick, located in Petaluma, Sonoma County California during August of 2018.
Object ID: EN09
Object Name: Dujardin-Salleron Ebulliometer
Original Inventor: Broussard-Vidal , French
Patent date: 18 June 1845
Obtained by WHP: 2018
WHP Ebulliometer in storage box.
Inside the cover of the storage box.
Jules Salleron (1829-1897)
Jules Sallerson was born on 18 May 1829 in Troyes, France in the Champagne region, located on the Seine River about 87 miles southeast of Paris. He was the third son of a merchant and his wife, Alexandre Salleron and Flore Rosalie Myon.
Jules Salleron was trained in the workshops of Lerebours & Secretan, a famous nineteenth-century French optical and scientific instrument-making firm based in Paris, formed in 1845. Salleron followed the physics courses promulgated by Victor Regnault, who was a French chemist and physicist, one of the most famous French experimental scientists of the nineteenth century.
Salleron opened his business in 1855, and by 1860 he occupied the Hotel du Président Lamoignon, a historic sixteenth-century mansion located in the Marais district in Paris, which now houses the Bibliothèque Historique de la Ville de Paris. He was a general maker of precision instruments for “science and industry”.
In the earlier part of his career, Jules made innovative meteorological instruments. In 1858, he produced a standard barometer providing an approximation to one thousandth of a millimeter and most of the equipment of the meteorological observatory at Parc Montsouris. The observatory was located in the 14th arrondissement and set up by Hippolyte Marie-Davy, a physicist and director of the observatory from 1873-1887. As stated above, most of the equipment was designed and made by Jules Salleron.
Hippolyte Marie-Davy
Ebulliometer Salleron-Dujardin (1891)
Jules Edouard Dujardin (1857-1947)
Dujardin joined Jules Salleron in his precision instrument company circa 1880 and eventually took over the company in 1889.
Jules Salleron and Jules Dujardin were honing the work of their predecessors, and, as stated, the two firms merged to form Dujardin-Salleron in 1889, according to the Bulletin of the Scientific Instrument Society, No. 150 (2021).
The Salleron ebulliometer was developed circa 1870 and has always been improved and tested. It is the simplest device to directly test the alcoholic content of dry wines with normal composition. When the two firms merged, the name of the ebulliometer became Dujardin Salleron. Therefore, the Wine History Project ebulliometer must be from post 1889.
Dujardin wrote this book in 1892.
Publisher was J. -B. Bailliere et fils, Paris.
Dujardin joined Jules Salleron in his precision instrument company circa 1880 and eventually took over the company in 1889.
Jules Salleron and Jules Dujardin were honing the work of their predecessors, and, as stated, the two firms merged to form Dujardin-Salleron in 1889, according to the Bulletin of the Scientific Instrument Society, No. 150 (2021).
The Salleron ebulliometer was developed circa 1870 and has always been improved and tested. It is the simplest device to directly test the alcoholic content of dry wines with normal composition. When the two firms merged, the name of the ebulliometer became Dujardin Salleron. Therefore, the Wine History Project ebulliometer must be from post 1889.
Some instruments which had been invented by Salleron were improved, and several new apparatuses were introduced in the catalogue. Together with his sons (Rene and Lucien) the newer, enlarged editions of the catalogue were published several times (1900, 1905, 1912, 1923, 1928). The latter two editions in ’23 and ’28 were published after Rene and Lucien joined the company.
Dujardin was very successful. One could find all the possible instruments and devices with illustrations detailing the instruments and their use for the chemical, physical, microscopical analysis of wines, spirits, beers, ciders, vinegars as well as apparatus for determining the quality of corks. Glasses and goblets of different size and shape for wine-tasting were also available.
This version of the wheel from 1953.
Apart from catalogues, Dujardin wrote several treatises and two interesting historical booklets: one concerning distillation and the other the alcoholometry. He directed the firm until 1920, when he was succeeded by his sons. The Dujardin family left the business in the 1980s, but the firm, since 2012, is in Noizay, a small village 220 kilometers southwest from Paris. The company continues to produce and commercialize instruments, apparatus, equipment, furniture, glassware, chemicals for oenological laboratories and the alcohol and winemaking industry. Many instruments are modern but the firm still produces and sells traditional instruments such as glass hydrometers and Salleron’s ebulliometer.
Ebulliometry is mentioned in several general books on winemaking. The wheel/ruler provided with the ebulliometer is known as the Dujardin-Salleron wheel.
Conclusions
The ebulliometer is an important instrument for accurately determining the alcohol content of beverages. Thanks to the principle of boiling solutions, this device offers reliable and accurate results, contributing to the quality control and regulation of alcoholic beverages. Its importance in the wine industry makes it an essential tool for ensuring compliance with standards and ensuring production consistency in the industry.
The instrument continues to be a cornerstone in testing wine for alcohol content, playing an essential role in the food industry.
Photo of a new Dujardin-Salleron Ebulliometer.
Sources
http://www.winegrowers.info/wine_making/Alcohol.htm
“Chronology of Illustrious Figures in the Viticulture and Oenological Field” , found at: https://www.darapri.it/approfondimenti/cronologia-personaggi-illustri-in-campo-viticolo-enologico/
https://www.californiawinemuseum.com/
“Un Glorioso strumento per l’analisi enologica: l’ebulliometro”, by Mario Castino; the test reviews historical development of alcohol measurement tools in enology, highlighting early ebullioscopes, their limitations, and improvements with diagrams of ebulliometers, found at: https://www.darapri.it/wp-content/uploads/2017/01/ebulliometro.pdf
https://www.impetodivino.it/blog/ebulliometro-di-malligand
A video by VanArnam Vineyards, July 29, 2023 on how to use an ebulliometer.
“Salleron and Dujardin: A long-lasting story in the recent history of scientific instrument industry”, by Paolo Brenni Bulletin 150 Found at: www.scientificinstrumentsociety.org
