And with emulsions on the brain, you guessed it--each sauce relies on some kind of emulsion to hold it together.
You're probably most familiar with hollandaise and mayo. Both of these sauces are egg-based, meaning they use eggs as the binder in their emulsion.
You may have made some of these other sauces without even realizing you were practicing fine French cuisine! They are flour-based sauces, and each starts off with a roux of equal parts of butter and flour cooked over medium heat. Different kinds of liquids are whisked into the roux, forming a stable emulsion and a creamy thick sauce.
- Bechamel: roux + dairy, usually milk or cream
- Veloute: roux + white stock (usually chicken stock, but it could also be fish stock or vegetable stock)
- Espagnol: roux + brown stock (usually veal stock where the bones have been browned before making the stock)
The same basic recipe for all of these sauces can be used to build an infinite number of other sauces. Bearnaise is simply a hollandaise with the addition of tarragon and shallots, and aioli is just as simple as adding garlic to mayonnaise. The flour-based sauces are a bit more versatile. They can be served as stand alone sauces drizzled on a dish before serving, but more often they are the starting point for things like hearty soups, velvety fondue, and creamy pasta sauces. In particular, espagnol is the base for many cajun dishes like catfish etouffe and gumbo!
(Photo Credit: BBC Good Food)