Beef broth is the flavorful liquid made by simmering beef, vegetables, and aromatics. It's used as a base for soups and is added to stews and braises and also sauces. Homemade beef broth is usually preferred, but the store-bought variety is more convenient for most people.
Though broth and stock are often used interchangeably, stock makes greater use of bones. Broth may be made with meat still on the bone, but its distinguishing flavor comes from the meat itself. Compared with stock, it has a lighter body and a more distinctly meaty flavor.
You can usually substitute beef stock; beef bouillon (reconstituted); chicken broth; vegetable broth.
Look for beef broth in cans and in aseptic cartons. You can also find some brands frozen. Your best bet for selecting store-bought beef broth is to sample a few varieties. Look for an authentic beef flavor, subtle vegetal notes, and a rounded consistency. Lower-salt versions are preferable, as they let you control the overall amount of salt in the finished dish.
Most store-bought beef broth can be used right from the package. Frozen beef broth may be concentrated and will need to be mixed with water. Be careful when reducing beef broth; its beefy flavor will become more concentrated, and so will its salty flavor; consider cutting back on the amount of salt if using store-bought beef broth.
Unopened broth will keep for a year at least in a cool, dry place. Once opened, broth will last up to a 5 days in the refrigerator; to keep track, it's a good idea to mark opened packages with the date. Frozen beef broth will keep for months.