Are McDonald’s* hamburgers immune to natural processes like rotting? There’s some evidence that they are, but a truly scientific inquiry into the matter has been lacking – until now. J. Kenji Lopez-Alt of Serious Eats tested nine different hamburgers of varying sizes (both homemade and from McDonald’s) to find out. Contrary to popular belief, the non-rotting phenomenon isn’t due to the mysterious chemical composition of the burgers. “[T]he burger doesn’t rot because its small size and relatively large surface area help it to lose moisture very fast,” writes Lopez-Alt. “Without moisture, there’s no mold or bacterial growth. Of course, that the meat is pretty much sterile to begin with due to the high cooking temperature helps things along as well. It’s not really surprising. Humans have known about this phenomenon for thousands of years. After all, how do you think beef jerky is made?” (HT: Chris Blattman) *Interestingly, the McDonald’s website doesn’t use the word “McDonald’s” at all except in its copyright tag; the golden M does all the work. [%comments]
Why McDonald's Hamburgers Don't Rot
TAGS: food
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It may be high temperature and increased surface area, or it may be the microscopic organisms are just smarter than humans and know not to eat ‘food’ from that particular company. That’s my guess.
“*Interestingly, the McDonald’s website doesn’t use the word “McDonald’s” at all except in its copyright tag; the golden M does all the work. ”
That may be true for the homepage, but they use “McDonald’s” throughout the website.
There are a few comments along the lines of “why doesn’t the bread mold, my bread always grows mold.”
If you wrap your bread in plastic, or store it somewhere damp, it will mold. If you store unwrapped, it will get stale, and petrify. Once this happens, it will not grow mold.
Exactly. Where there’s water, there’s life–biology 101. Leave the hamburger in its golden wrapper and it’ll look just like the horrifying, alien-like loaf of bread I neglected for weeks on the top of my refrigerator. Were I to have left the selfsame loaf of bread out in the open, I’d have had bread crumbs.
doug m:
There is more to decay than mold.
Rats, Mice, Roaches, other Insects, Bacterial Colonies, Protozoans, Fungi, Flatorms, Roundworms. Parasites, Putrefecation, Water Damage, UV Damage, Heat Damage, Oxidation.
Its like a party on the potato salad and Everyone is invited!
To confine all decay to mold is like saying lighting causes ALL human deaths.
Twinkie makers have engineered their product well. Too bad GM cannot similarly engineer product longevity.
Dr. Monica Hughes, a PhD biologist, has a couple of excellent posts and videos up of a thorough, well controlled debunking on this issue. McDonald’s burgers and fries definitely do rot with enough moisture present.
http://sparkasynapse.blogspot.com/2010/11/of-mushrooms-molds-and-mcdonalds-day-17.html
Thanks Jon.
Anything rots, given sufficient moisture. Compact discs will rot. Rocket fuel will rot. Oil slicks will rot.
Here are the Day 26 results of my experiment. http://sparkasynapse.blogspot.com/2010/11/of-mushrooms-molds-and-mcdonalds-day-26.html
Results for the fries, whether homemade or McD’s. No water: no microbes. A little water: fungi. A lot of water: little to no fungi and lots of bacteria.
Conclusion: food pretty much rots, if given sufficient moisture, whether it comes from McDonald’s or anywhere else.
The inhibition of various species of microbes at certain levels of water activity (a measure of the vapor pressure of water in the food and the immediate environment) is something the food industry has known for a long time:
http://en.wikipedia.org/wiki/Water_activity
I hope you had a nice Thanksgiving.
Do you remember how I was going to have a visual aid with that McDonald’s happy meal burger? Well, I found this article in New York Times and now I am not sure if I should do it.
There is a similar version of the test with just the fries, though.
So I am wondering if the burger is a good choice.
Thank you.
Maja