Calvisano, a small town between Venice and Milan, is home to Agroittica Lombarda, the most prolific caviar farm in the world, producing more than 20 tons of eggs each year under the Calvisius brand. Perhaps Calvisius has an edge because of experience: the farm (originally in collaboration with the University of California at Davis) has been raising white sturgeon, a Pacific species valued for its pale flesh and dark, briny roe, since the 1980s, and it produced its first batch of white sturgeon caviar in 1996. (The firm also raises osetra sturgeon and is developing beluga caviar.) Or perhaps it's the conditions: unlike some farms that continually recycle the same water through their fish tanks, Agroittica Lombarda treats its sturgeon to a constant supply of fresh groundwater. The pristine environs are reflected in the flavor of the roe, which is delicious. The white sturgeon eggs are buttery and mild, followed by a clean salinity. Meanwhile, the more complex osetra caviar (pictured at left) reveals rich flavors of walnut and banana. Experts advise that caviar of this quality should be enjoyed unadorned. Yet, I can't help but crave it in an egg-white nest, just as I ate it when I was a kid. An ounce of Calvisius white sturgeon caviar costs $61, and an ounce of osetra costs $89, plus shipping. Visit www.calvisiuscaviar.com.