People all over the world eat and enjoy Caviar every day, and yet many don’t know exactly what it is, or are often confused by what is marketed and sold as caviar, when according to purists, is not caviar at all. We hope to be able to clear that confusion by having caviar defined.
By definition, Caviar is fish eggs (also known as roe) with its fatty tissues and membranes removed through a filtration process. The remaining caviar is then preserved and cured by being sparingly salted with non-iodized salt, an ancient tradition passed down through the ages that is still used to this day.
Despite the fact that all female fish produce and lay eggs (a necessity of reproduction), not all fish roe is used to make caviar (for the most part, not all roe is actually suitable for caviar production).
Historically, caviar was extracted from 25 species of fish in the Acipenseridae family (most commonly known as sturgeon) with the majority of fish species in this group collectively referred to as true sturgeons. In fact, for the die-hard caviar aficionado, only the roe from the sturgeon (and only the sturgeon) is considered true caviar, even though there are dozens of caviars made from the roe of different fish around the world on the market today. According to the UNFAO (the United Nations Food and Agriculture Organization), fish eggs not obtained from the Acipenseridaespecies of fish, are not actually caviar but instead caviar substitutes. Indeed, depending on whom you ask, or where they are from, caviaris used to describe the roe from more commonly available fish such as salmon, paddlefish, trout, steelhead trout, tuna, lumpfish, whitefish, as well as other species of the sturgeon family of fish. This is similar to the argument of what constitutes champagne.
How is Caviar graded?
That said, despite the opinion of caviar purists, different types of caviar does indeed exist (not just sturgeon), and is a delicacy all over the world. But how do consumers tell the difference between one and another? Simple- caviar is graded based on how it is processed and the size of the eggs used. Traditionally, caviar grades derive from the type of sturgeon from which the eggs were extracted, and they are as follows:
Beluga: Are the most recognized type of caviar due to the size of the eggs (about the size of a pea- the largest) and are either gray or black in colour, and are known to be the most expensive type of caviar largely due to the rareness of Beluga sturgeons (found in the Caspian Sea). Beluga caviars can be further sub-divided into two additional sub-grades as well.
Osetra (Osetrova): A little smaller than Beluga and are either gray, grayish-green, or brown in colour (mostly because Russian sturgeon change colour as the fish matures). Osetra caviar is said to have a nutty or creamy walnut taste. Osetra caviars can be further sub-divided into two additional sub-grades as well.
Sevruga: Are the smallest eggs and are green-black in colour, and come from the Stellate sturgeon- and are the strongest tasting of the three grades of caviar. Sevruga caviars can be further sub-divided into two additional sub-grades as well.
In addition to the above three grades, Pressed eggs are also considered a grade of caviar. Pressed Caviar is caviar paste that is made by pressing the fish eggs that rupture or break when traditional caviar is packed.