Three D.C. City Council members yesterday criticized top officials of the Washington Convention Center for not forcing the center's food service contractor to purchase more food supplies and equipment from District of Columbia companies.

Council member Betty Ann Kane (D-At large), noting that construction of the new center was pushed in part because of the economic benefits it would bring city businesses, said she was surprised to discover that the center's private food concessionaire was purchasing many supplies from firms outside the District.

"We've got very good meat places, plant stores and several paper suppliers in the District," Kane said during a hearing of the council's Committee on Housing and Economic Development.

Questions about the food service operator's purchases came up as the committee considered a request to have the city include $2.4 million in the coming year's budget to buy kitchen equipment installed in the center by the food service contractor.

Last August, the center awarded its $20 to $40 million food services contract to a white-controlled joint venture--made up of Sportservice Corp., a Buffalo-based firm, and Waters Catering Service Inc. of Rockville--after efforts to give the contract to a minority-controlled company failed, largely because of problems in raising the $2.4 million required to build and equip the center's kitchen.

The $98.7 million center, which officially opened in December, was forced to require the food service contractor to build the kitchen because of restrictions imposed by Congress. After the kitchen was built, it was agreed, the city would have the option of purchasing the equipment.

Kane said she is against the city's spending $2.4 million for the equipment at a time when social programs and other needed services are being cut in Mayor Marion Barry's proposed 1984 budget. She said the city would also lose the increased leverage it has to force the contractor to do more business with city firms if it bought the equipment right away.

Committee chairman Charlene Drew Jarvis (D-Ward 4) and council member Frank Smith (D-Ward 1) also urged convention center officials to be more forceful in requiring that the contractor do business with minority-controlled D.C. firms.

Convention center general manager George W. Demarest Jr. and his chief assistant, Michael C. Rogers, pledged to monitor the contractor's purchases more closely.

Rogers said the main incentive to have the city buy the kitchen equipment is because the fee Sportservice pays the city would double from 12.2 percent of gross receipts to 25.2 percent. Rogers said that the city would recover the $2.4 million cost by 1986.

Jarvis said in an interview that she probably will recommend that the council approve the purchase. She noted that Sportservice did receive informal assurances from center officials that the city would buy the equipment.

In other action, the committee approved a proposed new unemployment compensation law that would, among other things, raise taxes paid by employers and reduce the time period employes can collect benefits from 34 weeks to 26. The bill would not apply to those presently collecting benefits.