Fact Checking McDonald's Non-Aging Burgers: This Time for Real

The meme of McDonald's non-aging hamburgers has reached epic proportions. But thus far, efforts to investigate the validity of and reasons behind the non-decaying and (seemingly non-organic) meat and buns have been anecdotal, have failed to isolate control variables, and have been plagued by hungry cats.

Fortunately, J. Kenji Lopez-Alt of Serious Eats' blog A Hamburger a Day is endeavoring to implement some actual scientific method to determine why and how McDonald's hamburgers don't age:

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I wanted to test the following things: Whether it's something in the beef that's keeping the burgers from rotting. Whether it's something in the bun that's keeping the burgers from rotting. Whether it's some sort of magical alchemic reaction that keeps the burgers from rotting only when a McDonald's patty is in contact with a McDonald's bun. Whether it's the size of the patties that are preventing the burger from rotting. Whether it's the storage environment that is preventing the burgers from rotting. I figured that would cover most of my bases and prove whether there's anything inherently different about a McDonald's burger and a regular homemade burger.

To accomplish this, Lopez-Alt is using the following materials:

A plain McDonald's hamburger, stored on a plate at room temperature. A homemade burger of the same weight and dimensions as a McDonald's burger (I was fine using a store-bought bun, because who bakes their own buns?) A McDonald's hamburger patty on a store-bought bun. A homemade patty on a McDonald's bun. A McDonald's hamburger stored in its original packaging. A McDonald's hamburger stored in a zipper-lock bag. A plain Quarter Pounder. A homemade quarter pounder.

The experiment is currently underway; in a few weeks, we'll have some serious data on the subject of what really happens to McDonald's burgers when they're left out.

Photo by J. Kenji Lopez-Alt