A stock is a flavorful liquid made by gently simmering bones and/or vegetables. Stocks are helpful when it comes to giving something flavor. There are many different types of stocks for example beef, fish, and chicken are all different types of stocks.
9 types of stock include:
White stock, which is a clear pale liquid made by simmering poultry, beef, or fish bones
Brown stock, is an amber liquid made by simmering poultry, beef, veal, or game bones that have been browned first
Fumet is very similar to fish stock, this is a highly flavored stock made with fish bones
Court Bouillon is an aromatic vegetable broth used for poaching fish or vegetables
Glace is sometimes referred to as "glaze" this is a reduced stock with a jelly-like consistency, made from brown stock, chicken stock, or fish stock
Remouillage is a weak stock made from bones that have already been used in another preparation, sometimes used to replace water as the liquid used in a stock; remouillage is the French word for "rewetting"
Bouillon is the liquid that results from simmering meats or vegetables' also referred to as broth
Jus is a rich lightly reduced stock used as a sauce for roasted meats
Vegetable stock is usually made form mirepoix, leeks, and turnips. Tomatoes, garlic, and seasonings may also be added to flavor or darken the stock, but tomatoes must be strained with a cheesecloth or filter so that no seeds or skins get into the stock. This is referred to as tomato concasse. A chef might roast the vegetables or add a large amount of a particular vegetable, such as mushrooms for mushroom stock.
Stocks are a very important part of cooking because they form the basis of many dishes, especially soups. It is very important to know how to make stocks properly because you get rich flavor from it.