Researchers led by a team from Princeton University have found that a layer of bubbles or foam on top of a liquid–like the kind found on a latte–help keep it from sloshing by a factor of ten due to friction with the container.

A layer of foam on top of a drink or any other container of liquid can dampen its internal movement. 

This research, led by a team from Princeton University, was inspired after one member was told that her latte did not need a lid stopper.

To test this assertion, they added water, dishwashing liquid Dawn, and viscosity enhan