Tuesday, November 18, 2014

Louis Pasteur

Photo Credit: Britannica
Diseases are great. Diseases are fun! That is, unless you catch them, in which case they are significantly less great and even less fun.

Louis Pasteur is great, and Louis Pasteur is fun—and that’s a definite statement. Known as the god/father of microbiology, Louis Pasteur is probably one of the coolest scientists of the nineteenth century. And, if you’ve ever had a glass of milk, then you have something to thank him for.

In reality, you don’t even have to drink the milk to see it on the carton: down near the bottom there’s a little schpiel that will say “PASTEURIZED MILK” and maybe the grade and some other great facts to help you bond with your milk.

And you’re like, “Great. Leave me alone; I want to blow bubbles in my milk before Dad gets home.”

But hear me out.

If you don’t know anything about pasteurization, let me sum it up for you in simple terms (and we’ll talk about milk, because I know about milk):

  • milk has bacteria in it, really gross pathogenic bacteria that makes you sick if you ingest it
  • milk men and women take the pathogenic milk and put it in a heater
  • we heat up the milk to 154.4 degrees Fahrenheit for thirty minutes
  • the heat affects the bacteria that’s present in the milk; the enzymes in the milk are denatured 
    • proteins that keep the bacteria functioning are heated into a different shape so they can no longer do their jobs—this is also the reason that you could die from a fever
  • the denatured bacteria dies—but some bacteria remains unaffected by the heat
  • the pasteurized milk is shipped out, and we keep our milk in the fridge to prevent the unaffected bacteria from spoiling our milk too fast

(Of course, people still drink fresh milk sometimes. They probably don’t die. But, in today’s society where we don’t all own cows and we don’t want to go to the store every day, it works out to take out the bacteria to make it last longer.)

But wait, there’s more.

The thing is, this guy who actually started developing the pasteurization process, Louis Pasteur, was actually a pretty awesome guy—practically a scientific superhero. Check it out.

Louis Pasteur was a chemist, first and foremost, and principal among his interests was germ theory. Back in the day, a popular theory ran around of spontaneous generation: that is, stuff came out of nowhere because God said, “Let there be maggots.” And thus maggots were.

So maggots randomly appeared on meat, food went bad for no reason, and mice came out of dirty underwear (no, I’m serious, we watched this video in Bio Monday morning. It’s worth your two minutes).

Louis Pasteur was like, “Don’t be ridiculous,” and experimented with beef broth to show that there was something in the air that we couldn’t see that made food go bad. He proved it, too: his broth left out to the open air would spoil and turn nasty (I’m sure you’ve left something out too long, too) while the broths that were sealed or swan-necked (twisted over) didn’t spoil nearly as fast.

However, he had more on his plate than mere beef broth. No, Louis Pasteur studied fermentation as well!

I just studied a whole unit on cellular respiration, so I’m not going to give you that speech, but I will say this: if you’ve heard about fermentation, then it’s probably been in relation to one of two things: your sore muscles after you’ve exercised, or beer.

Plot twist, Louis Pasteur actually came up with initial pasteurization processes for wine and beer, not for milk! While studying different organisms that multiply with oxygen (aerobically) or without (anaerobically) in his fermentation studies, Pasteur used his methods to make his alcohol safer to drink.

But that’s not all.

Monsieur Pasteur’s studies in microbiology saved the silkworm industry in France—knowing nothing of silk worms himself, Pasteur spent five years studying silk worms, breeding them, and then coming up with methods to prevent their contamination with harmful microorganisms so that France, not to mention every other country with silk worms, could keep making silk.

And, on top of that, he came up with vaccinations for Anthrax (independently of Koch, by the way), chicken cholera, and rabies.

Yes, rabies. He dried out a bunch of rabid rabbit skulls in his yard and then stuck pieces of their brains in a nine-year-old kid’s stomach. (And that’s still pretty much what they do to you if you get rabies today.)

But, truly, if he were around today, I would give this guy an air five, because apparently he didn’t like to shake hands.

So, what did you learn today?


  1. One of my favorite lines from Polite Dissent (an awesome blog, by the way) is as follows:
    "Louis Pasteur was a French scientist from the 19th century. Every time you drink milk and don’t die, you owe it to him (assuming your drinking pasteurized milk – if it’s raw milk, then good luck to you and say hello to Brucellosis for me). "


    1. XDD Yes! I love when I don't die from drinking milk. Now I have to go look up Polite Dissent...

  2. So I wandered over here (heh, pun not intended) from Sometimes I'm A Story, and this really got me. Yeah, Pasteur is like a saint - I laughed so hard at your "Let there be maggots" line! Really cool post; oh, and if you take reader suggestions, may I propose Rosalind Franklin next time?

    1. I love wanderers, wanderers are the best. :) So welcome to the other half of the blogging I do. Pasteur was awesome, but I'm also of the opinion history shouldn't be boring so I'm glad I made you laugh! And sure. At the moment I have no idea who Rosalind Franklin is but I'm certainly up to the challenge. ;)