Wal-Mart Stores, Inc.’s U.S. grocery business generated about $140.6 billion in sales last year, up 2.1 percent from the previous year, as the biggest retailer continued its expansion in fresh produce, meat, dairy products and other foods.

Groceries accounted for 54 percent of Wal-Mart’s U.S. sales in the company’s fiscal 2011, which ended Jan. 31, Wal-Mart said in a March 30 filing with the U.S. Securities and Exchange Commission. That was up from 53 percent in 2010, the first year that groceries claimed more than half of Wal-Mart’s U.S. revenue. The figures exclude Sam’s Clubs stores.

Based on those percentages, groceries produced $140.6 billion of Wal-Mart’s net U.S. sales across all merchandise categories totaling $260.3 billion last year. Last year’s net sales were up 0.2 percent from $259.9 billion the previous year, Wal-Mart said in the filing, known as a 10-K.

Bentonville, Ark.-based Wal-Mart expanded fresh food departments in recent years, using aggressive discounts to draw customers from traditional supermarket chains. Wal-Mart is the largest U.S. food retailer, controlling at least a fifth of the market, according to analysts.

Wal-Mart sells more groceries than Kroger Co. and Safeway Inc., the two largest U.S.-based traditional supermarket chains, combined. Kroger’s and Safeway’s sales totaled $123.3 billion in the companies’ most-recent fiscal years.

While Wal-Mart’s food business grew, its broader sales languished recently, in part because the retailer lost customers to dollar stores. Wal-Mart’s comparable-store sales, a key gauge of retailer performance, fell 1.5 percent for the U.S. in fiscal 2011 following a 0.7 percent decline in 2010.

Mike Duke, Wal-Mart’s chief executive, in February said the company will continue to add Supercenters and also open more small stores in urban markets such as Chicago and Washington, D.C.

At the end of January, Wal-Mart operated 2,907 U.S. Supercenters, up from 2,755 a year earlier. Most Supercenters offer full food departments. Wal-Mart also has 189 smaller “Neighborhood Markets.” Including Wal-Mart’s traditional discount stores, the company had 3,804 locations at the end of January, up 49 from a year earlier.

Groceries also account for the majority of Sam’s Club sales. In the March 31 filing, Wal-Mart said groceries were 55 percent of the warehouse chain’s total sales of $49.5 billion for fiscal 2011. Based on that percentage, Sam’s Club had grocery sales of $27.2 billion.