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Who doesn't enjoy toasting a marshmallow after a delicious cookout? Those warm, sweet summer night bonfires scream for toasting marshmallows!

How do you toast the perfect marshmallow? This debate has been around since toasting marshmallows began who knows when!

Whether you enjoy your toasted marshmallows barely warmed or golden brown or charred black, a marshmallow undergoes a six-step transformation before it becomes a true, toasted marshmallow. This is rather interesting as it all occurs so quickly that it is hard to believe this simple practice goes through such a scientific process.

Once you place the marshmallow on the stick, the following occurs:

The Swelling:
As the marshmallow heats, the moisture in it expands, causing the marshmallow to swell.

The Escape:
As the moisture expands, it blows tiny holes through the marshmallow and escapes as steam.

The Sugar Rush:
Depleted of moisture, the marshmallow is now a sucrose char. Oxygen in the air rushes to its surface -- it is ready to burn.

The Flame on Stage:
Oxygen diffuses from the air to the outer surface of the marshmallow. At the surface, carbon reacts with the oxygen, producing a blue flame. This terminology for this is a burning in the diffusion-limited mode.

The Oxidation Stage:
Simultaneously, carbon atoms grab oxygen atoms, producing carbon monoxide, the carbon dioxide.

The Oxyinterruptus Stage:
I know - quite a word! I am not even sure how that one is pronounced! However, it does have a purpose. Pulling the marshmallow from the fire and blowing it out interrupts the oxidation process. This creates soot, evidence of incomplete combustion.

Source:  Reginald Mitchell, an associate professor of mechanical engineering and combustion science specialist at Stanford University, explained this process in an issue of Sunset Magazine.