Louis Pasteur and the Birth of the Food Safety Pasteurization Process

Without Louis Pasteur's inventions, our milk, dairy, juice, and egg products would spoil much faster and wouldn't be as safe to consume.
Trevor English

Louis Pasteur has had a greater effect on your life than you might think. He not only came up with the food preparation process now known as pasteurization, but he also made discoveries in the world of vaccines and helped further modern germ theory. 

Pasteur's Early Life and Studies

Louis Pasteur was born in 1822 in the Jura region of France. Growing up, he was just an average student who took interest in drawing and painting, going on to earn a bachelor of arts and a bachelor of science at the Royal College of Besancon. Following these degrees, he got a doctorate as well.


Following his formal higher education, he spent years doing research in the fields of chemistry and medicine. In 1848, he was selected as a professor of chemistry at the University of Strasburg where he met his wife and wed her a year later. 

It was all of this backstory that would lead Pasteur on a path of great scientific discovery.

Discovery of Pasteurization

Pasteur was appointed the dean of the science faculty at the University of Lille in 1854 where he investigated problems surrounding alcohol fermentation. Specifically, he worked closely with a local distillery.

As you might be able to guess, this was Pasteur's first step on the path to studying and gaining a deeper understanding of the fermentation process. The famed chemist began investigating nearly everything surrounding the fermentation process, like the production of lactic acid.

In 1857 he left to return to a teaching role in Paris where he presented experimental evidence demonstrating that living organisms were involved in the fermentation process. He was even able to demonstrate how each specific organism affected each process of fermentation. His evidence presented in 1857 would go on to be the basis of germ theory.

This discovery of specific organisms being involved in fermentation led Pasteur to the discovery that fermentation could be stopped by passing air, or rather oxygen, through a fermenting liquid. This process is now known as the Pasteur effect.

Pasteur deduced that because oxygen was the deciding factor in stopping fermentation, the microbe responsible for the process must only be able to function in a zone lacking oxygen. This impeccably led to the introduction of the terms aerobic and anaerobic to describe organisms relation to the presence of oxygen.

As the chemist was making headway in the realm of fermentation, he went on to make other important discoveries in the textile industry.

Pasteur Saved the Silk Industry 

In 1865, Pasteur was able to prove that microbes were attacking silk manufacturer's silkworm eggs. These microbes were shown to be causing a disease, one that could be eliminated if the microbes were then eliminated. 

For context, prior to 1965 this disease was wreaking havoc across the silkworm industry in Europe, even spreading to China and Japan. By the time Pasteur ultimately discovered the root cause, the silkworm industry was faltering across all of Europe and Asia.

One side effect of Pasteur's research into the subject was that he became an expert silkworm breeder, perhaps one of the foremost in the entire world. 

His ultimate solution to eradicating the disease was one of prevention. He developed a process that prevented new silkworm eggs from being contaminated by the disease-causing organisms. After several years of this being implemented, the disease was practically eradicated and is now a standard in the industry.

Louis Pasteur and the Birth of the Food Safety Pasteurization Process
Louis Pasteur. Source: Public Domain/Wikimedia

Medical Discoveries

In 1879, Louis Pasteur made his first discovery in the realm of vaccines, particularly one for the disease "chicken cholera." While working around the chickens, he accidentally exposed them to a lower potency form of the culture and saw that they became resistant to the actual virus. It was this "accident" that led Pasteur to further his own ideas on germ theory and help develop vaccines for other diseases.


After this first foray into vaccines and medicinal research, he focused his efforts into studying anthrax, a disease that had killed many sheep and humans across Europe. Pasteur believed that his concept of vaccination could be applied to anthrax as well.

He developed a lower potency, attenuated, culture of anthrax and after a round of initial financial support, delivered the culture to 70 farm animals. These animals proved to be immune to anthrax and the experiment was a huge success. 

Following his successful discovery of the anthrax vaccine, he started investigating pathogenic microbes further, eventually pioneering the field of infectious pathology. After all this research, it is now said that Pasteur invented vaccines. 

Following all of this success for the scientist, he wanted to conquer one last big hurdle: Rabies.


Pasteur started focusing his medical research efforts towards rabies in 1882. He started infecting different animals with rabies trying to find a way to attenuate the microbes to create an active vaccine-like he had done in the past. What ended up happening was Pasteur created an inactive form of the disease, though he didn't know it at the time. In essence, Louis Pasteur had discovered inactive vaccines but was completely unaware at the time.

By 1885, he successfully vaccinated a 9-year-old boy who had been bitten and infected by a rabid dog. As you might be able to guess, this miraculous cure brought Pasteur near-instantaneous fame. It kickstarted a fundraising venture to create the Pasteur Institute in Paris.

Louis Pasteur and the Birth of the Food Safety Pasteurization Process
The Pasteur Institute. Source: Public Domain/Wikimedia

How He Discovered So Much

As you can probably tell after reading about everything that Pasteur accomplished in his life, the discoveries made at his hands were vast.

He was quoted as saying "There are no such things as pure and applied science; there are only science and the application of science."

This quote summarizes just why Pasteur was able to discover so much. After making an initial discovery, he would try and determine any new ways to apply that discovery to the world around him.