Wal-Mart, the largest grocer in the United States, has already hired 30 field managers and plans to hire hundreds more over the next three years, people familiar with matter said in recent days. Their job is to train workers and take other steps to improve the fresh food offering in stores, the people said.

The move was first disclosed at an annual meeting of suppliers last week in Indianapolis, the people said. That meeting was not open to the public.

Wal-Mart spokesman Lorenzo Lopez said on Wednesday Wal-Mart was in the process of hiring managers “to help ensure quality and consistency in our fresh operations.” He declined to comment on the number of people who would be hired.

Wal-Mart has placed a renewed emphasis on fresh food under the strategy of Greg Foran, head of the company’s U.S. operations. Foran sees a better fresh food offering as key to reviving sales growth.

The move to install a new layer of managers comes as Wal-Mart faces growing competition for grocery shoppers from national and regional supermarket chains like Florida-based Publix Super Markets Inc and Texas-based H-E-B.

The new managers will oversee the fresh food operations at about 10 stores each, a Wal-Mart executive told suppliers at the annual meeting last week, one of the people familiar with the matter said.

Wal-Mart has about 4,600 stores across the United States.