The Kroger Co.'s earnings before onetime charges climbed 20 percent in its first quarter, lifted by strong sales of private label products that it makes for sales in its stores.The nation's largest grocery chain said it earned $276.5 million, or 33 cents per share, before charges in the quarter that ended May 20 compared with $231 million, or 27 cents a share, a year ago.The results were 2 cents a share higher than analysts surveyed by First Call/Thomson Financial had expected.Kroger shares to $1.062, or by 5.7 percent, to close at $19.75 on the New York Stock Exchange.Sales increased 6.2 percent to $14.3 billion from $13.5 billion.Including one-time costs, the company's profit tumbled to $106 million for the quarter from $206.9 million a year ago. The company had charges related to its acquisition of the Fred Meyer stores and other costs that depressed earnings before taxes by $280.4 million in the latest quarter and $40.3 million a year earlier.Spokesman Gary Rhodes said the company benefitted from an increase in sales of its private label products that it makes for its stores.At the end of the first quarter, the company operated 2,319 supermarkets and department stores in 31 states under such names as Kroger, Fred Meyer, Ralphs and Smith's. Kroger also operates 792 convenience stores, 397 jewelry stores and 42 food processing plants.