Associated Food Stores Inc. had its biggest year ever in fiscal 1991, ended March 30, as sales rose 1.97 percent to an all-time high of $745.75 million for 52 weeks, up from $731.34 million for 53 weeks last year.

Total return to member retailers was $35.32 million, up 7.26 percent from the $32.92 million reported in fiscal 1990 - the highest return in its 51-year history.In Associated's 1991 annual report, Chairman Gerald W. Day and President D. Gill Warner told members the record sales and return to member retailers came despite one less week in the year, sale of eight Alpha Beta stores and closure of a three-store chain in Las Vegas.

It was a "tremendous year" for expansion of retail member stores, said Day and Warner. In every division of the company, members opened new stores, expanded existing ones and took over operation of existing facilities formerly operated by other entities.

A total of 356,300 square feet was added to member facilities during the year and, since March 30, another 233,500 square feet have been opened or are under construction.

That and other growth could push member expansion by nearly 600,000 square feet which, in a two-year period, would add some 1 million square feet to member stores.

"We congratulate the members who have built new stores or expanded their existing facilities and we welcome the new members who have changed suppliers and have joined the Associated family," said Day and Warner.

Associated's assets total $153.44 million, up from $144.76 million last year, and "remains in a very strong financial position," the two executives said.