The Sticky Science of Syrup
Syrups like molasses, honey, and maple syrup are essentially just plain sugar and water, with a thick, viscous consistency that's equally good for soothing sore throats and smothering pancakes. This raises the question: Why are these foods so sticky? As MinuteEarth's Emily Elert explains in the video below, it all boils down to chemistry.
Water and sugar are both made up of molecules with tiny charges, which act like magnets around oppositely charged atoms. However, water is made of tiny H20 molecules, which slide past each other as they transfer from one surface to another. Meanwhile, sugar's molecules are much larger, and lock together into a solid when they're at room temperature. This means that only a few charges are exposed on the outside of each crystal.
"Because solids don't flow, only a few exposed charges are close enough to the surface to stick to it, which isn't enough to make the crystal as a whole stick," Elert says. "But when a sugar crystal gets dropped in water, its molecules detach from each other and reattach to H20s. Only when lots of sugar gets added do the sugars end up sticking to each other, too. ... Those big, bulky sugar molecules can't slide past each other nearly as easily as H20s can, which is why syrups like molasses are thick and viscous."
Learn more syrup science by watching the video below.