Classic Stocks
Knowing the classic French stocks is a valuable reference for all cooks.
I would recommend to anyone that wants to learn stock making to begin with the classic preparations: white stock, brown stock, fish fumet, and vegetable stock.
It is useful to learn why these recipes use different techniques; once you understand them you will be able to make modifications based on the ingredients you have available or produce a certain result.
There are three components to stock: bones, aromatics, and herbs.
Bones
Animal bones and cartilage contain collagen, which can be extracted from the bones via cooking in water at a low temperature for an extended period of time. Collagen breaks down into gelatin and is what gives stocks their silky mouthfeel. A well-made stock should thicken quite a bit when cold. Classic stocks use one type of bone to make a stock: veal, chicken, pork, or fish bones. Shrimp and lobster shells can be used as well to make seafood stock or bisque.
Aromatic Vegetables
Aromatics are vegetables that deliver deep and complex flavor and aroma when heated. The standard for aromatics in French cooking is a classic mirepoix, which is a 2 : 1 : 1 ratio of evenly diced onion, celery, and carrot. The size of the dice depends on how long the stock will cook. A small dice for fish, medium dice for poultry, and large dice for veal or beef.
For a lighter colored stock, you can use a white mirepoix which is a 1 : 1 : 1 : 1 ratio of onion, celery, parsnip, and leek. There are regional variations of the classic French mirepoix in all cuisines that are influenced by the local vegetables and culinary traditions.
For more detail on aromatics, click here.
Herbs
The third component of stocks are herbs. These are added in the final 45–60 minutes of the stock and will add additional flavor and depth. The classic recipe calls for a bouquet garnis which is celery leaves, parsley, bay leaves, and thyme tied together with butcher twine. The purpose of the twine is so that the chef may remove the bouquet when they feel the stock has been adequately seasoned with the herbs. For our purposes, we can simply add direct to the stock in the last 45 minutes of cooking without the twine, and strain it out at the end with the aromatics.
For recipes and details on herb bouquets, click here.
Simmering
Add your bones and enough water to cover them. If you are using a standard 8 ½ qt stock pot, 2-4 lbs of bones should fit in the pot and add enough water so the bones are covered, this will be about a gallon.
Bring cold water slowly up to a very low simmer; the heat is probably lower what than you think it needs to be. It should be between 180-185 degrees. If you do not have a thermometer, look for bubbles that break the surface occasionally. The French use the term “fremir” which means “to tremble” to describe how the bubbles should look. 180 degrees F is enough heat to extract flavor and collagen from your ingredients. This is the goal of stock—not to boil, which will cause it to become cloudy and over reduced.
Skimming
A foam will start to form on top of the stock. Skim this off and discard it as it builds up. The foam is called “scum” and is made up of denatured proteins (similar to the proteins in egg whites) and impurities that will make your stock cloudy and cause it to sour sooner. You may also have some fat rise to the top from the animal trim that can be skimmed off.
Skimming will make your stock clear and have a longer shelf life. It will also help you keep the heat lower, as the foam will trap heat and cause the water temp to rise. You want to avoid this, to keep your stock from boiling.
Types of Stocks
White Stock
Made by combining all the ingredients with a cool liquid (usually water) and simmering over gentle heat. White stock is most commonly made with chicken bones, but can also be made with veal, pork, or beef bones.
Brown Stock
Made by browning the bones and mirepoix in enough fat to produce a rich dark color, either by roasting in the oven or on the stove top. Brown stock can be made with veal, beef, pork, lamb, chicken, or duck bones.
Fish Fumet
Made with fish bones to produce a fish stock. Aromatics are lightly sweated, and the overall cooking time is much less than other stocks. Often made with the addition of dry white wine.
Vegetable Stock
Made with non-starchy vegetables and cooked for a shorter time than animal-based stocks. Flavor will be extracted from the vegetables and herb bouquet. But without the presence of animal bones, there will be no gelatin in the stock.