Fish stock is a flavorful cooking liquid made by gently simmering fish frames, backs, tails, heads, skin, and other trimmings in water with vegetables, herbs, and seasonings. Traditionally, fish stock is prepared much more quickly than meat or poultry stocks because the delicate fish tissues release gelatin and flavor readily during cooking. Lean white fish create a light, delicate stock, while salmon and other richly flavored fish produce a fuller, more distinctive broth. As the fish simmers, collagen is converted to gelatin while proteins, amino acids, minerals, and flavorful compounds move into the liquid, creating a nourishing base for soups, stews, sauces, grains, and seafood dishes.