Stocks and Broths
Stock is the flavorful liquid prepared by simmering ingredients in water. It form the base of many soups and sauces. Stocks are composed of
- bones—chicken, beef, fish, or veal. Bones and cartilage release both their flavor and a protein called collagen, which turns into gelatin and adds texture to the stock.
- mirepoix—aromatic vegetables. Generally in a 2:1:1 ratio of onions, carrots, and celery. Leeks and garlic heads are common additions.
- herbs. Typical herbs are parsley, thyme, bay leaf, and black peppercorns.
The term broth can be used interchangeably with stock, especially when it is bought from the store, but broth generally refers to stock as used in the finished recipe—essentially, the liquid part of a clear soup. Broth can also be used to distinguish the liquid when it is prepared with meat, as opposed to just bones.
Chicken stock is readily available in supermarkets, and in increasingly high quality, but you can make stock very easily and inexpensively at home. Store-bought stocks can contain excess salt, tomato paste, or other ingredients, and most stores don't carry types like veal broth or fish broth. Making it at home means you can control exactly which ingredients go into your stock.
Stock can be stored frozen. If you freeze it in small portions, you can simply grab however much you need and add it, frozen, directly into your recipe.
Basic preparation guideline
Place clean, washed bones into a large stock pot, taking up no more than 2/3 the volume of the pot. Cover the bones with cold water by an inch or two. Using hot water would allow the stock to come to temperature more quickly, but it can cause the pores in the bones to seal up, preventing the collagen from steeping out.
Bring the water to a simmer, uncovered. Do not stir the stock, and do not let it boil, or the fat and impurities (scum) will remain suspended in the water instead of floating to the top, resulting in a cloudy and greasy stock. If the bones do not remain submerged, add additional cold water. Skim any scum you see on the surface.
After 30 minutes of simmering, add the mirepoix. Use a ratio of 1 part mirepoix for every 3 parts bones (by weight), or adjust to taste. Add salt, if desired (though it is usually left out since stocks are used in other recipes). Continue skimming as the stock simmers.
Add herbs, loosely, tied in a bouquet garni, or placed in a sachet, 30 minutes before the stock is finished. When the stock is finished, skim, remove the solids, and strain.
Stocks can be defatting by skimming, with a fat separator, or by refrigerating and then removing the hardened fat.
Types and variations
If the above recipe is made with raw bones, it is a fond blanc, or white stock. These stocks usually use chicken bones. Total cooking time is 2–4 hours.
Roasting the bones and mirepoix until caramelized before using yields a fond brun, or brown stock. Deglazing the roasting pan and adding it to the stock also adds flavor. These stocks are traditionally made from veal bones, but beef or chicken bones can be substituted. Tomato paste can be added here for flavor, whereas it would discolor a white stock. Total cooking time is 4–8 hours.
Short stocks are used when regular stock is not available, or to augment the flavor of an existing stock. The bones are cut into smaller pieces, and, in the interest of time, the bones and mirepoix are sautéed rather than roasted. Total cooking time is 45–90 minutes.
Vegetable stocks simply replace the bones with more mirepoix. Total cooking time is 45 minutes to an hour.
Broths made with meat have the benefit of providing fully cooked meat for use in any recipe. To make a dark broth, sear the meat in a frying pan before adding. Total cooking time is 45 minutes to an hour, or when the meat is done.
Stocks made from fish bones should only be cooked for 30–45 minutes.
Stock (excluding vegetable stock, of course) can harbor bacteria if it is not kept cold or hot. If you are not using it right away, bring the temperature down as quickly as possible before refrigerating. This can be done with an ice bath in your sink or, as Alton Brown does it, with frozen water bottles.
Stock keeps in the refrigerator for a few days, but keeps in the freezer for months. As stated, you can freeze it in small portions, ready to be added directly into your recipes.