Franz Ritter von Soxhlet (January 12, 1848 Brno – May 5, 1926

Munich Munich ( ; german: München ; bar, Minga ) is the capital and most populous city of the German state of Bavaria. With a population of 1,558,395 inhabitants as of 31 July 2020, it is the third-largest city in Germany, after Berlin and Ha ...

) was a German agricultural chemist from Brno. He invented the

Soxhlet extractor A Soxhlet extractor is a piece of laboratory apparatus invented in 1879 by Franz von Soxhlet. It was originally designed for the extraction of a lipid from a solid material. Typically, Soxhlet extraction is used when the desired compound has a ' ...

in 1879 and in 1886 he proposed pasteurization be applied to milk and other beverages. Soxhlet is also known as the first scientist who fractionated the milk proteins in

casein Casein ( , from Latin ''caseus'' "cheese") is a family of related phosphoproteins ( αS1, aS2, β, κ) that are commonly found in mammalian milk, comprising about 80% of the proteins in cow's milk and between 20% and 60% of the proteins in hum ...

albumin Albumin is a family of globular proteins, the most common of which are the serum albumins. All the proteins of the albumin family are water-soluble, moderately soluble in concentrated salt solutions, and experience heat denaturation. Albumins ...

globulin The globulins are a family of globular proteins that have higher molecular weights than albumins and are insoluble in pure water but dissolve in dilute salt solutions. Some globulins are produced in the liver, while others are made by the immune ...

and lactoprotein. Furthermore, he described for the first time the sugar present in milk, lactose. The Soxhlet solution is an alternative to

Fehling's solution In organic chemistry, Fehling's solution is a chemical reagent used to differentiate between water-soluble carbohydrate and ketone () functional groups, and as a test for reducing sugars and non-reducing sugars, supplementary to the Tollens' reag ...

for preparation of a comparable cupric/tartrate reagent to test for

reducing sugar A reducing sugar is any sugar that is capable of acting as a reducing agent. In an alkaline solution, a reducing sugar forms some aldehyde or ketone, which allows it to act as a reducing agent, for example in Benedict's reagent. In such a reacti ...

s. He was the son of a Belgian immigrant. He gained a PhD at

Leipzig Leipzig ( , ; Upper Saxon: ) is the most populous city in the German state of Saxony. Leipzig's population of 605,407 inhabitants (1.1 million in the larger urban zone) as of 2021 places the city as Germany's eighth most populous, as ...

in 1872. In 1879 he became a professor of agricultural chemistry at the

Technical University of Munich The Technical University of Munich (TUM or TU Munich; german: Technische Universität München) is a public research university in Munich, Germany. It specializes in engineering, technology, medicine, and applied and natural sciences. Establis ...

.Soxhlet, Franz Ritter von
In: Neue Deutsche Biographie (NDB). Band 24, Duncker & Humblot, Berlin 2010, , S. 606 f.

References

* Rosenau, M.J.: The Milk Question, Houghton Mifflin Company, Boston, 1913. * Soxhlet, F.: Die gewichtsanalytische Bestimmung des Milchfettes, Polytechnisches J. (Dingler's) 1879, 232, 461 * Rommel, Otto: Franz von Soxhlet Münchener Medizinische Wochenschrift 73 (1926) 994–995 * Österreichisches Biographisches Lexikon, XII. Band, chwarzMarie – Spannagel Rudolf, Wien 2005

Writings

* Herzfeld: ''Franz von Soxhlet †''. In: Die Deutsche Zuckerindustrie Vol. 51, 1926, pp. 501–502. * Theodor Henkel: ''Franz von Soxhlet zum Gedächtnis''. In: Süddeutsche Molkerei-Zeitung Vol. 46, 1926, pp. 493–494 (m. Bild u. Schriftenverzeichnis). 1848 births 1926 deaths 19th-century German chemists 20th-century German chemists Scientists from Brno People from the Margraviate of Moravia Academic staff of the Technical University of Munich Moravian-German people {{Germany-chemist-stub