"The company has been a big disappointment," he said.
ConAgra shares have tumbled almost 16 percent in the past 12 months, compared with a 14 percent gain for the Standard & Poor's 500 Index. The stock gained less than 1 percent to $30.96 on Aug. 8, the most recent trading day.
Rodkin said Monday the company is improving its operations and has the right product portfolio to appeal to budget-minded consumers.
"We are beginning my last fiscal year at ConAgra Foods by making good progress, and I have deep conviction that we are on the right path to deliver sustainable, profitable growth," he said in the statement.
The fact that Rodkin will be at the helm for almost 10 more months suggests he's not getting pushed out, said Erin Lash, an analyst at Morningstar in Chicago. Rodkin, who previously worked at PepsiCo and General Mills, will be 63 when he retires next year.
Still, the new CEO faces the challenge of selling ConAgra's existing brands alongside Ralcorp's private-label foods - something the company hasn't proved it can do smoothly. ConAgra has a stable of well-known products, including Reddi-wip, Slim Jim and Hunt's. Ralston, meanwhile, sells food that retailers package under their own names.
Timothy Chen, an analyst at Rhino Trading Partners in New York, said in June that investors may push for a ConAgra breakup if the company can't demonstrate that it can better integrate Ralcorp with its existing brands.
ConAgra's fourth-quarter results missed its forecast, hurt by slow sales of consumer foods and shrinking profit at the private-label business. Its profit in the period amounted to 55 cents a share, excluding some items, short of the 60 cents that ConAgra had predicted. The results, which also prompted a fourth-quarter writedown of $681 million, sent the shares on their biggest one-day decline in almost six years.
The company is contending with pricing pressure in supermarket brands - an industry that's been growing but offers slim margins. Quarterly operating profit for that unit fell about $60 million in the fourth quarter from a year earlier.