Then this month, investigators zeroed in on another Georgia plant while probing a second bout of salmonella that began in the fall and has sickened some 500 people in 43 states, and may have contributed to at least eight deaths.
As health officials scramble to limit the effects of the latest outbreak, food safety advocates have renewed calls for increased testing at peanut processing plants. It's a costly and time-consuming proposition for an inspection process that, as an Associated Press review of state and federal procedures shows, already suffers from a lack of manpower and transparency, and from uncertainty over how much testing is enough.
Peanut butter had long been considered a relatively low risk for salmonella because roasting the peanuts properly kills the bacteria, and because peanut butter's low moisture content makes it a less fertile breeding ground for the virus than other foods, such as poultry or lunch meats.
There is no federal law that mandates the number of inspections that must be carried out each year at peanut processing facilities. The Food and Drug Administration contracts with states to perform inspections but allows them broad discretion when it comes to how they do them. The agency asks the states to base the frequency and nature of inspections on how risky a food is considered, giving priority to high-risk foods.
The states, in turn, rely on the companies to police themselves between infrequent visits from state inspectors. And a number of leading peanut butter companies won't specify what they do to keep their products from being contaminated.
Jif maker J.M. Smucker Co., Skippy manufacturer Unilever and Omaha, Neb.-based ConAgra Foods Inc., which makes Peter Pan, all said they have stringent food safety and quality control standards. But neither Unilever or ConAgra responded to the AP's questions about how often the plants test their finished product for foodborne illnesses or other contamination. Smucker's said it couldn't answer those questions for proprietary reasons.
None of those manufacturers is implicated in the current salmonella outbreak.
Authorities reassessed peanut butter's risk level in 2007, when salmonella was found in Peter Pan and Great Value peanut butters made at a plant operated by ConAgra in south Georgia. ConAgra officials later said jars were contaminated when moisture from a roof leak during a rainstorm and a malfunctioning sprinkler system mixed with dormant salmonella bacteria in the plant.
The FDA still considers peanut butter a low-risk food, though after the ConAgra outbreak, Georgia Agriculture Commissioner Tommy Irvin ordered state inspectors to start routinely testing peanut butter for salmonella.
This month, a facility in Blakely, a rural Georgia town that calls itself the "Peanut Capital of the World" and is an hour or so drive from the ConAgra plant, found itself at the center of the investigation into the deadly salmonella outbreak. Virginia-based Peanut Corp. of America, which owns the Blakely plant, distributes peanut butter to institutions such as hospitals and nursing homes. It also provides peanut paste to food companies, which use the product in cookies, cakes and other products available on supermarket shelves.
On Tuesday, federal officials said Peanut Corp. failed to tell inspectors that after samples sent to a contract lab for testing in 2007 and 2008 tested positive for salmonella, the company got a second opinion from another lab and sold the food after the secondary tests came back negative.
"Under the current regulations and laws, they are not required to share those records with state regulatory authorities or even with the FDA," said Oscar Garrison, Georgia's assistant agriculture commissioner, who oversees the consumer protection division.
"It's just basically a loophole that has been there," he said, noting that the law does prevent a company from shipping a product if it knows there is a safety risk. He also said the agriculture department plans to try to get the state law changed during the current legislative session to require companies to share those records with inspectors.
The Georgia Department of Agriculture performed two inspections last year at the Blakely plant, including one in October - a month after the first people fell ill with salmonella. They found relatively low-level violations, such as equipment that wasn't properly covered and dust buildup, but did not check for salmonella during either inspection, according to department reports obtained by the AP through an open records request.
Regulators in Georgia, Arkansas and Kentucky, where the three top commercial peanut butter brands are produced, said state employees carry out routine inspections at peanut butter plants at least once or twice a year. Officials in Arkansas and Kentucky - where Skippy and Jif are produced, respectively - review records kept by the companies. Samples of the finished product are not taken during routine walkthroughs unless inspectors have reason to believe there might be a violation.
Agriculture officials in Georgia, whose inspections are comparable to Arkansas' and Kentucky's, said last week that manpower and funding shortages limit the number and extent of inspections they can do. The state has 60 inspectors responsible for examining 15,000 sites, or about 250 food sources per inspector, ranging from individual ice machines to sprawling factories.
Companies should be required to do more testing on their own, said Caroline Smith DeWaal, director of food safety for the Center for Science in the Public Interest, a Washington-based nutrition advocacy group.
"Testing should be done regularly, which could mean lot by lot, or at least daily," Smith DeWaal said.
Good management practices established by the American Peanut Council, a trade association that represents all segments of the U.S. peanut industry, say tests "should be done on a regular basis," though they do not specify how often that means. The council's president, Patrick Archer, said this is because each company must design its own inspection plan, taking into account local laws.
"Testing is costly," said Mike Doyle, director of the University of Georgia's Center for Food Safety. "Companies have to be practical about it, as well as making sure they are providing the best possible protection for the consumer."
The following recalls have been announced: