U of I research raising the bar with caviar

Since the early 1980s, the Lemmon family has specialized in a scarce, niche food product that’s synonymous with luxury.

Their Magic Valley-based business, Blind Canyon Aqua Ranch, raises and processes white sturgeon caviar through its subsidiary, Idaho Springs Foods. It’s one of two Idaho caviar businesses that have earned the state a reputation for producing the crème de la crème of the precious commodity.

Since 1997, University of Idaho has played a pivotal role in shaping Idaho’s renowned caviar industry. Scientists at U of I’s Hagerman Fish Culture Experiment Station — part of the Aquaculture Research Institute — have spearheaded innovative studies and delivered vital technical expertise, contributing significantly to the industry’s reputation for outstanding quality.

It’s all about the water

The secret behind the Magic Valley’s caviar lies in producers’ access to a continuous flow of pristine spring water, where sturgeon are carefully raised. Caviar — sturgeon eggs cured in salt brine — can develop unappealing flavors when raised in earthen ponds or facilities with recirculating water. Idaho spring water eliminates those impurities, allowing the natural flavor to shine.

“Ours is a very clean flavor so that the buttery and nutty tastes really stand out. You don’t have any environmental influence,” said Linda Lemmon, general manager of Idaho Springs. “Distributors make certain to note that it’s Idaho white sturgeon.”

The Lemmons sell their caviar wholesale in large tins, which buyers repackage into smaller tins or jars ranging from a half ounce to 4 ounces each. A single ounce of their product can fetch upwards of $100 at retail.

Lemmon’s husband Gary ’77 is among the principal owners of Blind Canyon. Gary’s father, George, started raising Sacramento River white sturgeon in 1982. Five years later, the company joined a newly formed cooperative involving the Idaho Department of Fish and Game, Idaho Power and about a dozen aspiring commercial sturgeon farmers and other collaborators. Commercial operators were allowed to breed a few wild sturgeon removed from the Snake River each spring, retaining some of the fry for caviar and meat production while dedicating others for stocking the catch-and-release fishery. They also agreed to relinquish up to half of their live sturgeon to bolster the fishery in the event of a threat to the wild population.

Sturgeon are remarkably long-lived fish, capable of surviving for over a century. They can also grow to impressive sizes — the largest female in the Lemmons’ brood pool, spawned in 1993, now weighs more than 300 pounds.

Idaho produces about 4,400 pounds of caviar annually, placing it a distant second to California among U.S. states. Known for its lighter, olive- and brown-hued roe, often sporting white rings and spots, Idaho’s caviar stands in contrast to California’s signature black variety.

“Many chefs will tell you the white sturgeon here in Idaho produce some of the most sought-after caviar, particularly in the nation but internationally as well,” said Jacob Bledsoe, an assistant professor and aquaculture Extension specialist based in Hagerman.

Caviar harvest typically occurs when fish are between 14 and 16 years old, and processing caviar must happen quickly. They kill the fish, remove the ovaries, salt the eggs and seal them in tins all in under an hour. Cooked sturgeon meat has a dense texture, similar to swordfish, but with a mild flavor. Annually, Idaho Springs sells about 60,000 pounds of sturgeon meat to Magic Valley fresh fish wholesaler Riverence, which supplies chefs and retailers throughout the country, and another 40,000 pounds to First Ascent Fisheries, which delivers live sturgeon to small grocery stores in the Seattle area. Their fillets are also available at local restaurants such as the Turf Club in Twin Falls and Snake River Grill in Hagerman.

Caviar harvested at the ideal moment — just before the fish would deposit the eggs in nature — pops and melts in the mouth, retaining optimal flavor and quality. Harvesting just a day or two late can result in mushy, unusable eggs, wasting about a decade and a half of investment in a fish. The Lemmons use both biopsies and ultrasounds — an approach pioneered by U of I researchers — to monitor egg development.

Partnering with industry to advance sturgeon science

As a member of the College of Agricultural and Life Sciences Dean’s Advisory Board, Lemmon regularly collaborates with U of I scientists. When she has a research question or need, she reaches out to U of I experts, who design studies or draw on scientific literature — including research on other fish species — to provide informed answers.

Because sturgeon are less efficient than rainbow trout at converting feed into body mass — and require several years of feeding — developing cost-effective, species-specific diets is especially important. Researchers at U of I have focused on formulating sturgeon feed using plant-based ingredients and other alternatives to fish meal, which is costly and becoming harder to source due to overfishing. Their work also emphasizes optimizing nutrition while minimizing fat accumulation in the ovaries of female sturgeon. Eggs from fatty ovaries are harder to harvest, which can hurt caviar quality.

Clayton Mabey, a U of I doctoral student studying aquaculture, recently presented sturgeon dietary research at the World Aquaculture Society Conference in New Orleans, receiving a second-place presentation award. Mabey’s research was part of a three-year project funded through the Western Regional Aquaculture Center.

“We found out that sturgeon typically don’t need as much protein as rainbow trout or salmon, and they don’t need as much fat,” said Mabey’s advisor, Matt Powell, interim associate dean of research and director of the Idaho Agricultural Experiment Station. “We can use a diet that has a little more carbohydrate to spare the protein.”

U of I has also conducted extensive research into sturgeon genetics, disease prevention and methods to preserve and extend caviar’s shelf life. Their work includes refining best practices for egg handling, investigating factors that influence egg color, and studying what affects the proportion of female fish in sturgeon populations.

“The caviar here is typically graded as Grade 1, which is the highest grade you can get, and that’s not from the people here in the valley. That’s from people coming in from the outside and rating this caviar,” Powell said. “That all has to do with the very good diets we feed the sturgeon and the very clean water they live in.”