How Caviar is Harvested, Processed and Stored
When it comes to caviar, timing is everything. Three days before a female sturgeon is ready to spawn, her eggs are taut and flavorful. Taken too early, the eggs are gooey with fat and won't offer a trademark "pop" when eaten. Taken too late, and they'll be a milky, mushy mess.
It seems the freshest caviar is plucked from a live fish, so sturgeon are often stunned by a bonk to the head and then slit open while still alive. Once the ovaries are removed, they, too, are emptied of their contents. Although the process of harvesting roe may seem cruel, there's been no major public outcry over its practice.
Harvesting eggs is a delicate process often done manually because roe is fragile and easily damaged. The roe sacks, or ovaries, are opened and rubbed across mesh screens using gentle pressure from the palm of the hand -- this action separates the eggs from the membrane and they drop through the screen into a shallow tub. The eggs are then rinsed with cold water and salted. After several hours, the resulting brine is drained and the roe, which is now caviar, is packed in containers with airtight lids -- fresh caviar will keep for two to four weeks.
The term for lightly salted caviar is "malossol," and it has a salt content of less than 5 percent. Most modern malossol caviars, however, contain less than 3 percent salt. Caviar with a salt content up to 8 percent is aptly named "salted caviar" or "semi-preserved caviar." Although still fresh, this caviar sacrifices taste for longer shelf life. Lesser grades of caviar with up to 10 percent salt are compressed into jam-like cakes with concentrated flavor, called "payusnaya," that will keep for three months.
Some fresh caviar is pasteurized. To do so, small vacuum-packed jars of caviar are immersed in hot water for several minutes. Pasteurization decreases the risks of encountering a food-borne pathogen, such as Listeria, which can be especially harmful to pregnant women. It also creates a shelf-stable product that can withstand a year of unrefrigerated storage and shipment.
Fresh, unpasteurized caviar, however, must remain at a constant, chilled temperature when shipped. A high-maintenance delicacy, caviar also requires frequent attention during transport -- it has to be turned often so the fat evenly coats each egg.
If caviar seems like a simple affair, keep reading -- the subtleties may surprise you.