Home > Encyclopedia of Food & Culture > Pasteur, Louis

PASTEUR, LOUIS. Coupling true scientific genius with a talent for dramatic self-promotion, Louis Pasteur (1822–1895) rose from humble beginnings as the son of a tanner in a small French village to international fame before his death.

Pasteur was trained as a chemist, and his earliest work on the crystals of tartaric acid, a naturally occurring by-product of wine production, caught the attention of several established chemists, who promoted his career and helped him secure an appointment as professor of chemistry at the University of Strasbourg.

Arriving in Strasbourg in January of 1849, he met Marie Laurent, daughter of the university's rector. With characteristic decisiveness, Pasteur proposed marriage within a few weeks, and in May of that year he and Marie were married. He chose well: For the rest of his life, Marie Pasteur supported and assisted him in his work; often they spent their evenings together, with Pasteur dictating notes or letters to his wife.

The Pasteurs moved in 1854 to the university at Lille, a thriving industrial area of France. Pasteur encouraged the practical application of science to the industries around him. His efforts on behalf of a local manufacturer who made alcohol from sugar beets were his first serious study of fermentation.

Moving on to Paris, he assumed positions at his old college, the Ecole Normale Supérieure, and later at the Sorbonne as well. He was not provided with a research laboratory, so he set one up at his own expense in a cramped unused space. This included a compartment under the stairs so small that he had to crawl in on his hands and knees to check his cultures.

In 1863, Emperor Napoleon III asked Pasteur to assist France in combating various "diseases" of wine that often caused exported French wine to go bad before it reached its destination. Pasteur believed that the yeasts observed in wine were the cause of fermentation, a fact that was not understood by much of the scientific community. These living yeasts appeared so mysteriously that many chemists believed they were generated spontaneously. Pasteur devised ingenious experiments to demonstrate that the yeasts came from the atmosphere. His belief in germs as causative agents that could infect a new medium on contact was sustained in his later work with animal and human diseases.

Pasteur also observed that other microbes besides the wine yeasts were present whenever the wines soured. In fact, he and his assistants soon learned to predict the taste of a wine according to which microbes they spotted in it with their microscopes. Pasteur urged the winemakers to provide conditions conducive to the growth of wine yeast and not to that of other microbes. He suggested a prolonged gentle heating, which discouraged undesirable microbes without altering the taste of the wine. A jury of wine experts conducted a taste test at Pasteur's request to establish that the taste was unaffected by the heating. This technique, which is today regularly applied to all kinds of foodstuffs, especially milk, quickly came to be called "pasteurization." Pasteur took out a patent on this process, but he soon allowed it to pass into the public domain. Though less dramatic than his later work with diseases, pasteurization is perhaps Pasteur's greatest contribution to the safety of food throughout the world. Pasteur was not the first to preserve foods by heating and protecting them from contamination, but he extended the practice to a variety of foodstuffs and offered a theoretical basis for its success.

Pasteur also advised vinegar makers, as well as the French beer industry. He hoped to make French beer superior to German as a gesture of revenge for the Franco-Prussian War of 1870. He taught hygienic practices to France's silk industry and, less easily, to the medical profession. The germ theory was then successfully applied to the development of vaccines for anthrax and other animal diseases, and finally to prevent the development of the dread rabies in human beings.

Pasteur achieved all this by dint of persistent hard work. His was not a balanced life. His labors, his ambition, and his aggressiveness in promoting his theories and reputation may all have been culprits in his severe stroke at age forty-five, which paralyzed his left side and left him with a limp. However, he continued to work for another two decades before his increasingly frail health gradually slowed him down.

Despite stirring up a good deal of controversy, Pasteur was given many honors in his lifetime. He received scientific prizes and awards and was elected to the French Academy of Sciences, the Academy of Medicine, and finally the august Académie Française. In 1888, the private Pasteur Institute was established in Paris, funded by contributions large and small from all over the world. Pasteur's seventieth birthday was the occasion for a national jubilee, and at his death he was given a state funeral in Paris before his body was interred in a grand tomb at the Pasteur Institute.

Even before his death, Pasteur was regarded, especially in France, almost as a secular saint. His earliest biographies were hagiographic, in keeping with the preference of the late nineteenth and early twentieth centuries for heroes of mythic proportions. The current age, on the other hand, needs to debunk, demythologize, and deconstruct the legends of the past. Accordingly, a modern reassessment of Pasteur has been in progress since the late twentieth century, aided by material from Pasteur's private laboratory notebooks, which have been available to scholars only since 1971. In the end, when all the evidence is gathered and reconsidered, the popular view of him may be altered, but Pasteur will remain a human being whose unceasing effort, scientific imagination, and inspired intuition unquestionably improved the food we eat and the world we live in.

See also Fermentation; France: Tradition and Change in French Cuisine; Microorganisms; Food Safety; Wine from Classical Times to the Nineteenth Century.

Alice Arndt