of a cat on one end and the head of a dog on the other?
Well, CatDog is kind of like a surfactant: he’s got something
that’s attractive to both cats and dogs, which makes him a
kind of feline-canine ambassador, allowing the two to mix
together a little more easily. Culinary surfactants are
molecules that have one end that is attractive to water
(hydrophilic) and one that is attractive to oil (hydrophobic).
Common kitchen surfactants include egg yolks, mustard,
and honey, and it’s easy to see the work of a surfactant in
action.
The container on the left contains oil and balsamic vinegar
mixed in a ratio of 3:1. The one on the right has the same
ingredients, with the addition of a small amount of Dijon
mustard. Both containers were sealed and shaken vigorously
until the vinaigrette looked homogeneous. I then allowed
them to rest at room temperature for 5 minutes. As you can
see, the vinaigrette without the mustard separated much
more rapidly than the one with mustard.
At this point, you’re probably thinking what I’m thinking:
this is all very neat, but what difference does it make to my
salad? Good question.