Final answer:
The bones of younger animals are preferred for stocks because they contain more collagen. Beef or veal bone stocks should cook longer than fish bone stocks for richer flavors. If a stock doesn't cook long enough, it may lack flavors and gelatinous texture.
Step-by-step explanation:
The bones of younger animals are preferred for making stocks because they contain more collagen, a protein that helps create a rich and flavorful stock. Collagen is found in higher amounts in the bones of younger animals, making the stock more gelatinous and imparting a better mouthfeel.
A stock made from beef or veal bones should cook longer than a stock made from fish bones because the larger bones of beef and veal take more time to release their flavors and nutrients. Additionally, the longer cooking time allows the collagen in the bones to break down and create a more viscous and flavorful stock.
If a stock does not cook long enough, it may not develop the desired flavors, aromas, and gelatinous texture. The stock may taste weak and lacking in depth, and it may not have the same thickening power when used in sauces and soups.
Learn more about animal bones for making stocks