Paris: Victor Masson, 1860.
First edition, unopened in original printed wrappers, of Pasteur’s definitive proof that alcoholic fermentation is due to the action of a living organism (yeast), and is not a purely chemical process as most chemists since Lavoisier had believed. “What did this memoir add to the first deductions Pasteur had drawn from lactic fermentation? He now asserted that he was dealing with a living microorganism. This was his most original contribution. Having been unable to create life or to change it by means of molecular asymmetry, he had set out to study its reproduction. In doing so he had come to a revolutionary definition: Fermentation is the act of reproduction of the living germs that constitute yeast” (Debré, Louis Pasteur (1994), p. 105).
“In December 1857 Pasteur published the first in a series of abstracts, notes, and letters on alcoholic fermentation that culminated in a long and classic memoir of 1860 [the offered work]. Divided into two major sections, dealing respectively with the fate of sugar and of yeast in alcoholic fermentation, it inflicted on the chemical theory what Duclaux called “a series of blows straight from the shoulder, delivered with agility and assurance.” Pasteur established that alcoholic fermentation invariably produces not only carbonic acid and ethyl alcohol–as was well known–but also appreciable quantities of glycerin and succine acid as well as trace amounts of cellulose, “fatty matters,” and “indeterminate products.” On the basis of these results, Pasteur emphasized the complexity of alcoholic fermentation and attacked the tendency of chemists since Lavoisier to depict it as the simple conversion of sugar into carbonic acid and alcohol. If the alleged simplicity of the process had formerly been seen as evidence of its chemical nature, he argued, then its actual complexity ought now to be seen as evidence of its dependence on the activity of a living organism. In truth, the complexity of alcoholic fermentation was such as to prevent the writing of a complete equation for it, a fact which was only to be expected, since chemistry was “too little advanced to hope to put into a rigorous equation a chemical act correlative with a vital phenomenon.”
“However impressive this line of attack against the chemical theory, an even more decisive mode of argument derived from Pasteur’s ability to produce yeast and alcoholic fermentation in a medium free of organic nitrogen. To a pure solution of cane sugar he added only an ammonium salt and the minerals obtained by incineration of yeast, then sprinkled in a trace of pure brewer’s yeast. Although the experiment was difficult and not always successful, this method could produce an alcoholic fermentation accompanied by growth and reproduction in the yeast and the evolution of all the usual products. If any one constituent of this medium were eliminated, no alcoholic fermentation took place. Obviously, argued Pasteur, the yeast must grow and develop in this mineral medium by assimilating its nitrogen from the ammonium salt, its mineral constituents from the yeast ash, and its carbon from the sugar. In fact, it is precisely the capacity of yeast to assimilate combined carbon from sugar that explains why it can decompose sugar into carbonic acid and alcohol” (DSB).
Pp. 323-426 in Annales de chimie et de physique, Troisième Série, Tome LVIII, 1860. 8vo (226 x 142 mm), pp. 512. Original printed wrappers, uncut and unopened. Light crease and two small holes to front wrapper, else very fine.