Fish stock, or fumet, is among the most nourishing foods known to man and even more so if you use your head, er, I mean their heads. Fish stock is a mineral-rich cocktail of calcium, magnesium, phosphorous, silicon and sulphur. But more than that, fish heads deliver health benefits that a cow or chicken simply cannot. So, it is no wonder that this precious potion is a central ingredient in the gastronomy of all cultures that enjoy abundant seafood.
Ewww alert: The magic that a beady-eyed fish cranium delivers is in part due to thyroid glands and iodine. Mmmm, right? Well, anatomy lessons aside, iodine assists your thyroid gland in producing hormones which regulate metabolism. Add to all these heady benefits, the fact that fish stock is loaded with gelatin, a digestive aid. And, of course, for those suffering from one food allergy or another, fish stock is casein-free, egg-free, gluten-free, nut-free, sugar-free, yeast-free, anti-candida, and low-carb. Oh, and delicious.
Ideally, fish stock should be made from non-oily white fish such as sole, turbot, rockfish or snapper. A good fishmonger will save fish heads and bones for you if you ask. If the monger only has sections from large fish, ask them to hack them down to pot-sized pieces. Fish bones are surprisingly tough and your kitchen will thank you for not playing ninja at home.
The process to make fish stock is simple. My recipe takes more time than the average simmer-and-slurp variety (about an hour) but you will be rewarded for the extra effort. Slow and steady reduction creates incredible depth of flavor. The fish stock freezes very well for up to 4 months so make more than you need and freeze portions. Far from “fishy,” a well-balanced fish stock can be sipped on its own. But, don’t miss the opportunity to see it shine in Clams with Salsa Verde, traditional Paella Mixto, or as poaching liquid for fish.