Of course, all female fish lay eggs to reproduce, so they all have roe. However, not all fish roe is suitable for nor considered to be caviar. By most definitions and to a purist, true caviar comes from the sturgeon and the sturgeon alone.
The sturgeon is a saltwater anadromous fish (meaning it moves to freshwater to spawn) which makes its home in the Black and Caspian Seas between Europe and Asia, and also the Pacific Northwest and Southern Atlantic coasts of the United States.
The sturgeon can grow to over 3,000 pounds, but usually averages about 60 pounds. The flesh of the fish, as well as its prized eggs, is quite delicious.
The most prized caviar comes from the beluga, osetra, and sevruga varieties of sturgeon. Nowadays you will also find caviar from other fish varieties, including salmon, lumpfish and tuna, as well as in different forms.
More about Caviar: What is caviar? FAQ
How to identify real caviar
Caviar Varieties and Terms
Caviar Selection and Storage
Caviar Etiquette and Utensils
Finding Affordable Caviar
Caviar Cooking Tips
Caviar and Health
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