"With mayo, you start with liquid oil and end with something thick, something you spread," she says. Mayo and cream are both emulsions; two liquids that don't generally mix can be manipulated, using droplet size and careful combination techniques, to pseudo-blend. One liquid is still technically suspended in the other, but this happens on such a tiny scale that they seem to form a single, cohesive, creamy combo. "Having a proper emulsification can be part of a strategy to lower or replace saturated fats, because that nice structure can fix the texture problem," Proulx explains. Creating the right size of oil droplets can create the kind of satisfying, mouth-coating, fatty sensation we crave. Proulx says there are a lot of complicated spins on this idea that are still in their early, academic stages, but might one day be commercialized.