Tulkoff's Horseradish Products Co. Inc. of Baltimore was ordered to pay $10,000 in fines after pleading guilty yesterday to mislabeling its products by failing to list potatoes as an ingredient in its horseradish products between Sept. 4 and Nov. 2, 1984.

The charges arose during a routine Food and Drug Administration inspection in November 1984. FDA inspectors raised questions after finding 336 50-pound bags of potatoes behind a partition at Tulkoff's.

In a plea-bargaining agreement reached between the Justice Department and Tulkoff's, six of the 10 counts against the company's top two officers were dropped, but 10 counts against the company itself remained. The country's largest horseradish manufacturer agreed to pay the maximum allowable fine of $1,000 on nine counts and $900 on the 10th, said Ken Jost, the Justice Department attorney who represented the FDA. The court added a $100 assessment on one count, bringing the total to $10,000.

U.S. District Judge John Hargrove fined Solomon Tulkoff, 64, president of the family owned firm, and Martin Tulkoff, 51, vice president of operations, a total of $800 on the four remaining counts. The maximum penalties for the officers were $10,000 in fines and up to three years in jail.

Solomon Tulkoff would not comment yesterday on the specifics of the case. "We couldn't cover the entire thing enough to put the thing in perspective," he said. "If anyone came by the plant and we got a good crack at it, we could show them the facts. Trying to explain things is like throwing gas on a fire."

The company maintained that the amount of horseradish root in its products was greater than that found in competitors' horseradish. "Most of Tulkoff's competitors have a lot more water and liquid," said Bruce Alexander, Tulkoff's attorney.

The relative quality of the product didn't make any difference in the case, Justice Department officials said, because the department charged Tulkoff's with mislabeling the product.

The company admitted to using potatoes in its products from March 1981 to July 1983, said Jost.

In six federal court actions initiated by the FDA in 1985, U.S. marshals seized Tulkoff's products in Virginia, Georgia, Ohio, Texas, Louisiana, Minnesota and Massachusetts. Chemical tests on the product showed varying amounts of potato starch, sometimes almost 40 percent, the FDA said.

"The sale of prepared horseradish -- with the substitution of potato for horseradish root -- is fraud upon the unsuspecting consumer," the FDA said in its request for seizure, because "the price of potatoes is substantially less than the price of horseradish root."

The FDA said Tulkoff's used 181,600 pounds of potatoes in its horseradish to cut production costs and increase profits in 1984, and that the company inconsistently used labels that listed "vegetables" as an ingredient.

Immediately after the potatoes were discovered, the company voluntarily withdrew its horseradish from the market.