Where were all the senators at the reception in the Capitol recently dedicated to caviar. With champagne at hand to wash it down? Free caviar and champagne would draw a throng elsewhere. Instead guests were able to sample - and resample - surgeon eggs and smoked sturgeon at their leisure. A few senators appeared, Hawaii's Matsunaga and New York's Javits, among them. But Middle America was nowhere to be seen.

Hard-core elitists might claim it was a case of taste discrimination. The caviar had not been imported from Iran or the Soviet Union. It came from California as did the champagne.

The intention of the Californians who put on the show was to make Congress (and presumably the rest of us) aware that there is caviar to be mined out West beyond the gold fields in the waters of the Sacramento River. Only sports fishermen have the legal right to catch sturgeon in California rivers at this time. Limited amounts are processed for sale legally further north on the Columbia River, however.

Advocates of "aquaculture" (an increasingly hot political buzz word meaning, of course, farming the wealth of the sea from the University of California at Davis would like the federal government's said for a project to study the maturation cycle of the sturgeon and for experiments in artificial breeding. Sergi Doroshov, a Russians native now on the staff at Davis, is convinced sturgeon can be in essence, domesticated and milked like cows in two-year cycles.

"According to a university spokesman. California fish and game officials are interested in the project, but "considering conditions now (meaning in the aftermath of Proposition 13), we hope to work with federal funds."

S.I. Hayakawa, the state's Republican junior senator, seemed impressed. "I didn't know we were in the business of producing caviar, even for cocktail parties," he said.

The caviar in question had been processed by an infant firm eager to see this infant industry grow. Mats Engstrom and his wife, Daphne, launched their "gourmet seafood" firm, California Sunshine, Inc., only this spring.

Both come from Swedish back-grounds and share an inherited fondness for cured salmon and sturgeon, fish roe and crayfish. They are "exporting" these products to New York and Boston and have sent California crayfish to France and Scandinavia. The caviar challenge is irresistible.

"We've been selling it commercially on a very small scale," Mrs. Engstrom explained. "But ours will sell for $90 a pound in the stores. That's $3.75 an ounce. Fresh Russian caviar costs $10 to $12 an ounce."

In anticipation of the next question, she already was offering a comparative tasting of one-week and three-week-old samples of the West Coast product. She preferred the mild, younger version, though a number of the guests opted for the more forceful three-week-old sample. "It's like Camembert cheese," she said. "It gets stronger as it ages and the choice depends on what you are used to."

Mrs. Engstrom and Doroshov both insisted that West Coast caviar is a superb product, lacking only the reputation of that harvested from the Caspian sea. They did agree, however, that the Russians and Iranians do have an edge in processing expertise.

It wasn't always thus, though. The caviar industry should not be considered an infant industry, but rather one being re-born.In the last century sturgeon were harvested along the East Coast and vast quantities of their caviar were exported to Europe.

Perfection is elusive, even for the greatest of chefs. Take the case of the three-star chef and his hamburger experiment.

France's Jean Troisgros, the bearded half of the brother tandem that directs Restaurant Troisgros in Roanne, crossed the Atlantic last week to New York City. At the invitation of Warner Leroy, the guiding light of Maxwell's Plum and the Tavern on the Green, he cooked dinner Tuesday and lunch the following day for small groups of invited guests.

Working with the Taven's kitchen staff. Troisgros unveiled - among other dishes - a chicken salad with truffles and a fish "pepper steak" at the dinner. The luncheon began with cubes of fresh foie gras lightly dusted with small grains of pepper and plump fresh snails glistening from an aromatic parsley butter bath.

After the guests took their seats, hot oysters on a bed of seaweed arrived, topped with shreds of vegetables and a sauce representing the embrace of a buttery sun and a faintly creamy sea. Allowing only time for a chorus of sighs and the pouring of fresh wine, Troisgros sent in a rendition of his most famous preparation, salmon in sorrel sauce.

The green-flecked liquid on which the salmon rested was less creamy and more charged with lemon that that served in Roanne, but exquisite to taste, as was the barely cooked escallop of salmon. As they savored the sauce, Leroy helped the diners retain their dignity and limit their consumption of bread by having spoons passed.

As the wine changed from white to red a new plate appeared. On it were several morsels of tender pork loin, subtly flavored with tarragon, and an oval patty of faux fillet hache , known in translation as "chopped steak" or hamburger.

The port, delicious as it was, couldn't compete with the lingering tastes of Troisgros' gifts from the sea. The hamburger presented no grounds on which to raise the tricolor of France. It was thin, flat and over-cooked. The only signs of hand-crafting were an imprecise perimeter and a sense of seasoning on the tongue. McDonald's rather than a vision of hamburger heaven, had been its inspiration. How sad, except for one thing: it did serve as a vehicle for a fresh tomato puree of marvelous zest and flavor.

Host Leroy was inspired. "I know this can sell," he exclaimed. "We'll bottle it and call it catsup." Then, with a sesame-seed roll and a score of other diversions to surround it, people will ignore that dried-out piece of meat.

Who says Americans can't teach the French anything about cooking?