While their fundamental concepts may have been around for a long time, it was French chef Marie Antoine-Careme who first classified the French sauces into groups all based on four foundational sauces. These are the Mother sauces and are the basis for all other types of sauces. Of course, you do not have to attend culinary school to master these techniques: you could also get a taste for them by visiting France or eating at such places as Restaurant Sinclair in Montreal.
Before you can understand the French Mother sauces, you have to know about roux. Essentially, to make a sauce you need to thicken a liquid so it effectively coats the food. You can achieve this thickening by reducing the liquid (evaporating the moisture) but some sauces need a thickening agent.
This thickening agent is known as roux. Roux is basically just a combination of fat and flour cooked together before adding the liquid. Most of the time, the “fat” can be butter or oil but you can use just about any type of fat.
The most base mother sauce, perhaps, you will rarely find béchamel on a menu on its own. Bechamel is basically milk (or other dairy product) whisked with roux to make a white sauce. The Italian Alfredo sauce, then, is a type of Bechamel (albeit, not a French sauce). Because it is milk-based, the sauce is usually bland and that is why it is typically a base sauce to which other ingredients are typically added.
A basic brown sauce, this combines beef or veal stock, tomato puree and browned mirepoix (saute of carrots, celery, onion, and herbs) with a very dark brown roux. It is often the base for demi-glace and dishes like boeuf bourguinon.
The only sauce that does not require roux, hollandaise is thickened by the emulsion of egg yolk and melted butter. These two things normally don’t mix together, which is what makes this savory and delicate sauce one of the most desired in the world.
Made by cooking tomatoes down into a thick paste (it can also be thickened with roux), this traditional French sauce is typically flavored with pork and aromatic vegetables.
This is a light roux whisked together with clear stock (fish, chicken, or turkey). Of course, the resulting sauce will take on the same characteristics of the stock used. Its name—veloute—is taken from the French term for velvet, which is an appropriate description for this sauce’s light and delicate texture.