Chicago-based Beatrice Foods Co. yesterday announced plans for a consolidation it expects will result in a loss of about $200 million in the current quarter but eventually make the company more profitable. It will be the first time the company has reported "a loss of any kind, operating or on paper, in more than 30 years," said a spokesman.

The moves include realignment along marketing lines of its domestic companies and special, after-tax charges totaling nearly $280 million against earnings in the fourth quarter ending Feb. 28.

A leading manufacturer of food and related products with earnings of $390.1 million on sales of $9.02 billion in fiscal 1982, Beatrice hopes to increase profitability by disposing of peripheral businesses and combining others.

Beatrice already has divested about 60 companies representing sales of about $1 billion. It hopes to trim its ranks further from more than 300 member companies to between 50 and 100.

In New York, Marsh & McLennan Cos. Inc., the largest U.S. insurance brokerage, said it will divest all its significant insurance underwriting in 1983.

In 1982, those businesses had combined premiums and other revenue of approximately $220 million. They are Crusader Insurance PLC and English & American Insurance Co. Ltd., both based in the United Kingdom, and U.S.-based American Overseas group. Marsh & McLennan companies provide insurance brokerage, reinsurance brokerage, benefits consulting, investment management and other services.