PORTLAND – Jordan’s Meats, a major Portland employer for more than 40 years, will close Feb. 1, with a loss of 285 jobs, Tyson Foods announced Friday.

Tyson, based in Springdale, Ark., said the 65,000-square-foot plant it acquired three years ago was not a suitable candidate for additional investment.

Workers at the plant and its distribution center in South Portland, which is also being closed, will be encouraged to seek jobs at other Tyson locations, the company said.

“From a human standpoint, this is a very difficult decision, since it affects the lives of our team members and their families,” John Lea, Tyson vice president of consumer products, said in a statement.

“However, we have evaluated every possible economic scenario for this facility and because of its age, layout, proximity to raw materials and downtown location, it simply does not make sense for us to reinvest in it,” he said.

The plant has been operating at a loss, spokesman Gary Mickelson said.

The average hourly wage, he said, was $11.30 for production workers and $16.50 for maintenance workers.

The sliced meats and cooked roast beef produced at the plant and marketed primarily under the “Jordan’s” and “Kirschner” labels will continue to be sold in the region but will be made at Tyson plants in New York, Iowa, Oklahoma and Wisconsin, the announcement said.

Tyson, the world’s largest processor and marketer of chicken, beef and pork, took over the plant through its 2001 acquisition of IBP Inc.

The two-story plant is located on prime property between the edge of the Old Port district and the base of Munjoy Hill and is a block or two from the waterfront.

The Tyson announcement came almost to the day last year when it said it was closing meat processing plants in Augusta, with about 170 employees, and Manchester, N.H., where 550 people worked.

The company said at the time that it was aiming to improve manufacturing efficiencies and that it would be too costly to upgrade the Manchester plant.

The Augusta plant was roughly the same age as the Jordan’s Meats plant, having been built in 1960 by the Joseph Kirschner Co.