BELUGA Pale to dark gray in color, with a buttery flavor, beluga is the largest, most expensive, and scarcest of the basic caviar varieties. It takes about twenty years for this sturgeon to begin producing roe, much longer than for other varieties, but mature females can weigh 2,500 pounds, and up to 10 percent of that is roe.
OSETRA Osetra caviar can vary greatly in color and flavor, but in general it has a richer—some would say nuttier—flavor than beluga.
GOLDEN OSETRA The golden caviar that was reserved for tsars was either the pale eggs of albino sturgeon (various species) or the yellow eggs of the sterlet. Golden osetra, though, is simply amber-hued osetra roe (the lighter color is a consequence of the fish's diet). It is milder in flavor than dark osetra.
SEVRUGA Sevruga eggs are darker and smaller than those of beluga or osetra, and more affordable. Often preferred over other varieties by Russian connoisseurs, sevruga caviar has a more intense sea flavor.
PRESSED CAVIAR Thick caviar paste, called payusnaya, is made from the damaged or overly mature roe of various sturgeon species. Concentrated and salty, it is a Russian staple.
SALMON ROE Russians call salmon roe red caviar. Strong in flavor, this roe is often served with garnishes as an appetizer.