Mechanical engineers put an Oreo’s cream filling through a battery of tests to understand what happens when two wafers are twisted apart
Engineers at the Massachusetts Institute of Technology (MIT), US subjected cookies to standard rheology tests in the lab and found that no matter the flavor or amount of stuffing, the cream at the center of an Oreo almost always sticks to one wafer when twisted open. Only for older boxes of cookies does the cream sometimes separate more evenly between both wafers.
The researchers have designed a 3D-printable “Oreometer”, a simple device that firmly grasps an Oreo cookie and uses pennies and rubber bands to control the twisting force that progressively twists the cookie open.
“While Oreo cream may not appear to possess fluid-like properties, it is considered a ’yield stress fluid’, a soft solid when unperturbed that can start to flow under enough stress, the way toothpaste, frosting, certain cosmetics, and concrete do”, said the researchers.
The understanding gained from the properties of Oreo cream could potentially be applied to the design of other complex fluid materials.