Casual science experiments have revealed that McDonald’s burgers seem to last years without ever rotting, which happens for a simple reason: the restaurant’s cooking process.

McDonald’s burger patties are made thin so that they last longer. They have more surface area than volume, which helps dry out moisture and prevent bacteria when cooking.

The restaurant also insists that staff make burgers well done to reduce the moisture content even more, and the high cooking temperatures help eliminate any present bacteria.

It’s actually possible to make your own burgers at home using the same cooking techniques, which proves McDonald's doesn't have any chemical-based tricks up its sleeves.