People often use the terms soup stock and soup broth interchangeably. From a culinary view, these are two different items. Broth is designed for use in flavoring side dishes like rice or as a foundation for soup. By comparison, stock gets used in gravy and main dishes. Both soup and stock are valuable additions to any kitchen.
Stock has a fuller flavor than broth, and doesn't react the same for processes like deglazing. Stock has more gelee than broth, so it gathers all the wonderful drippings in the saute pan, binding them together.
In preparing broth, there's more meat than bones in the mix. Some chefs recommend using stew hens for this creation. By comparison, stock has far less meat and more focus on bones. Typically for a chicken stock, for example, the bones of the bird get roasted then cooked in water with herbs and vegetables until the bones release gelee, which takes about 6 hours.
The intention with broth is providing crisp, intense vegetable or meat flavor. That's why it's favored for side dishes that would otherwise be bland. By comparison stock has depth, less seasoning, and a richer or heartier feel when consumed. It's not unusual for restaurants to have freshly made stock on hand for use daily.
Both stock and broth have very similar preparation methods and common ingredients. They each begin with water, celery, carrots, parsley, bay, thyme, onion and pepper. Additionally, meat stocks and broths feature chicken, beef, veal, venison, hen or pork. Vegetable stock and broth adds other vegetables into the mix like broccoli, tomato and cauliflower.
Put stock bones for roasting and boiling with carrots, onion and celery in a 400 degree oven for one hour before moving into a stock pot with enough water to cover the meat and herbs. Slow cook to extract the gelatin.
For about 5 pounds of meat and bones, use three medium onions, three carrots and two to three stalks of celery. Add a bay leaf, 1 teaspoon of parsley and 1 teaspoon of thyme.
Skim the fat from the top of the stock while you're cooking. Do not boil. After about six hours, the stock is ready. Strain and store in the refrigerator. If you're not going to use the stock immediately, freeze it.
The process for making broth is very similar to stock. Begin with a whole piece of meat or poultry on the bone. For 4 pounds you'll want one onion, two carrots,two pieces of celery, five peppercorns, a bay leaf, and three sprigs each thyme and parsley. Put everything into a large pan with 4 quarts of water. Bring everything to a low rolling boil, then reduce the heat letting everything simmer. Skim any grease off the surface of the broth, and continue to cook for one hour.
Remove the chicken and continue to let the mixture reduce down for another hour. Cool and strain, storing in the refrigerator or freezer for use.