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Welcome to Brainstuff, a production of IHeartRadio.

Hey, Brainstuff. Lauren Vogelbaum here.

Here in the northern hemisphere, the weather is getting warmer and thus cookout season approaches,

promising arrays of grilled foods and accompanying side dishes and salads. In lots of places, some of those salads are bound to be the

type that consist of stuff bound by mayo. Maybe a pasta salad or potato salad, maybe sandwiches

with chicken, tuna, or egg salad.

Manez is a thick sauce or dressing that's yellowish-white in color and tastes creamy despite

containing no dairy product. But how does that work? Today, let's look at the science and history

behind mayonnaise. In addition to being used as an

ingredient in the aforementioned cold mixed salads, mayo can show up as a spread on sandwiches

unto itself, or as an ingredient in casseroles, or in dips, alone, or mixed with other

sauces or seasonings for veggies, French fries, and other

dippable things. It has a creamy mouth feel and a mild, slightly zippy flavor. That texture

and flavor come from the fact that mayo is made from some kind of acid, like vinegar or lemon

juice, in an emulsion with a liquid fat, like olive oil or another vegetable

oil. The emulsion is bound together with something bindy, traditionally raw egg yolk,

and salt and various spices might be added for flavor. Emulsion is the term for an even mixture of two liquids that don't generally mix,

like oil and water, or in this case, oil and vinegar, or lemon juice. If you put equal parts of

oil and vinegar in a jar and shake them up, they'll beat up and appear to mix for a minute

or so, and then they'll start separating

out again. The molecules of water that the vinegar is primarily made up of do not want to bind to

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