A delicious delicacy at all times

Black caviar has long enjoyed a well-deserved reputation as the best, most nutritious, delicious, and gourmet fish product.
Do not believe it if you are told that supposedly, in Rus', black caviar has long been a delicacy for the elite. This is not entirely true. Princes and boyars did not seriously consider it a delicacy, preferring to see golden pike caviar on their tables.
The caviar of sturgeon fish contains a significant amount of complete proteins (22-37%), fats (14-18%), vitamins A, D and group B, as well as substances necessary for the human body - lecithin and cholesterol.
Black caviar has always been divided into several varieties. Thus, from the end of the 17th century until the 19th century. (before 1861) officially in trade practice they distinguished caviar:
1) granular,
2) pressed,
3) troishnaya,
4) yastiknaya.
Moreover, each of the main types could be divided into commercial grades: premium, first, second, depending on the degree of freshness and delicacy of salting (except for yastiknaya, which was always of one grade).