How To Prepare a Stock

There are a few basic rules which are commonly practised while preparing the stock and they are;
The stock ingredients are simmered by adding them to cold water. This process of simmering,  promotes the extraction of collagen, which may be sealed in by hot water.
Stocks are simmered gently, with bubbles just breaking the surface, and not vigorously boiled because if boiled it will become cloudy and not clear.
Salt is not added to a stock unless needed in the recipe, since most of the stocks are just made as a base to make soups and sauces.
If both meat and vegetables are used  in preparing the stock, meat is added first before vegetables and the scum that arises is skimmed and removed.  Only after removing the scum from the meat, vegetables and other ingredients are added to the simmering stock.
If pork or mutton is used, the cook might need to remove the fat, which can be done after the stock is finished and cooled. The fat which floats, separates, and solidifies into globs of lard within the stock can be removed easily.
These stocks can be frozen and stored in air tight containers in the Freezer for an indefinite period but are better tasting when used fresh.