Prof. Berta Levavi-Sivan of the Hebrew University's Robert H. Smith Faculty of Agricultural, Food and Environmental Quality Sciences and Dr. Avshalom Hurvitz have successfully reared Israel's first sturgeon. In the past, the Caspian Sea was the world's main source of sturgeon that produces the black fish roe delicacy. However, over-fishing and pollution have led to dwindling fishing yields in the region.
Prof. Levavi-Sivan and Hurvitz began rearing the fish eight years ago when they brought fertilized sturgeon eggs to Israel from the Caspian Sea. According to Sivan, it takes eight to fifteen years for the female sturgeon to reach puberty and start producing eggs, while male sturgeon reach puberty after four or five years.
Before the age of four, it is impossible to tell the gender of the fish. In order to determine this, an endoscopy is routinely carried out on the fish every year. Once the gender of the fish is determined, they are then separated. Male sturgeon will be sold as fish on the market, while the female sturgeon will be kept in order to produce caviar.
The average female sturgeon can produce US$3,000 worth of caviar. This is proving to be big business for Kibbutz Dan in the north of Israel, where 40,000 of the sturgeon are now being reared in outdoor pools. Managing director of 'Caviar Galilee' in Kibbutz Dan, Yigal Ben-Tzvi, estimates that by 2010, the company's annual revenues will reach US$7.3 million.
While there is significant demand for caviar in Israel among the country's sizeable Russian population, the intention of the producers is to market the fish for export to Europe and North America.
Prof. Levavi-Sivan is also now looking for ways to speed up the puberty process of the female sturgeon in order to reduce the time it takes to produce the caviar.
Sturgeon – and hence caviar - is not generally considered to be kosher, due to the fish's apparent lack of scales. Kosher fish must have both fins and scales in order to be deemed kosher.
However, Prof. Levavi-Sivan, who has undertaken similar fish-rearing projects in Uganda and the Palestinian Authority, suggests otherwise. "If you ask me, it's kosher! I can even prove it has scales," she says, insisting that the sturgeon does in fact have tiny scales that can be viewed with a stereoscope.
A number of Jewish sources – including the 13th century Jewish rabbi and scholar Moses Maimonides – approved the kashrut of a fish called the esturgeon. However, it has yet to be determined whether this is the same fish as the sturgeon.
So, while kosher caviar may be a long way off from hitting Israel's supermarket shelves, the researchers hope that in the meantime, Israeli caviar will at least prove to be a profitable export overseas.
Rebecca Zeffert | alfa
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