Of all foods from the waters, the most expensive and luxurious are fish eggs. Caviar, the salted roe of the sturgeon, is the animal kingdom’s truffle: a remarkable food that has become increasingly rare as civilization has encroached on its wild source. Happily, sturgeon farms are now producing good caviar, and a variety of other fish eggs are available as affordable and interesting alternatives.
The ovaries or “roes” of fish accumulate vast numbers of eggs in preparation for spawning: as many as 20,000 in a single salmon, and several million in a sturgeon, carp, or shad. Because fish eggs contain all the nutrients that one cell will need to grow into a hatchling, they’re often a more concentrated form of nourishment than the fish itself, with more fat (between 10 and 20% in sturgeon and salmon caviars) and large quantities of savory building-block amino acids and nucleic acids. They often contain attractive pigments, sometimes bright pink or yellow carotenoids, sometimes camouflaging brown-black melanins.