Federal health officials had traced one source of salmonella contamination to the plant, which makes peanut butter products for large institutions and peanut butter paste used by food manufacturers in everything from cookies and crackers to cereal and ice cream.
At least 85 companies had reportedly purchased peanut products from the Georgia plant, and 30 had been "urged" to run their own tests for the bacteria, the AP reported.
It is still not clear whether the salmonella was found at the plant is the cause of the massive outbreak, health officials said Friday, but testing continues.
The concern mainly is about peanut paste, since it is used in dozens of products, from baked goods to cooking sauces. Initially, federal and state investigators had focused on bulk containers of peanut butter sold to institutions such as nursing homes, but not to supermarkets, the AP said.
"Now it turns out, it's not just institutions," said Michael Hansen, a senior scientist with Consumers Union, said late last week.
The strain of salmonella involved with the outbreak has been identified as Salmonella Typhimurium, the most common of the more than 2,500 types of salmonella bacteria in the United States.
The recalls come two years after ConAgra recalled its Peter Pan brand peanut butter, which had been linked to at least 625 salmonella cases in 47 states.
On Sunday, ConAgra issued a notice that none of its products were at risk this time because the company does not buy from Peanut Corp. of America.
To learn more about salmonella, visit the U.S. Centers for Disease Control and Prevention.
SOURCES: Jan. 18, 2009, news release, Ralcorp Frozen Bakery Products; Jan. 17, 2009, news release, Perry's Ice Cream Co.; Jan. 17, 2009, news release, Hy-Vee Bakery; Jan. 14, 2009, news release, Kellogg Co., Battle Creek, Mich.; Jan 10, 2009, online statement, Peanut Corp. of America; Associated Press; Atlanta Journal-Constitution