IOWA CITY, Iowa — An Iowa company has agreed to pay $6.8 million in fines for selling old eggs with false labels and the tainted products that caused a nationwide salmonella outbreak in 2010, according to a plea agreement released Monday.

Quality Egg LLC, once one of the nation’s largest egg producers, is expected to plead guilty Tuesday to charges of bribing a U.S. Department of Agriculture inspector to approve sales of poor quality eggs, selling misbranded eggs and introducing adulterated food into interstate commerce. The company’s owner, Austin “Jack” DeCoster, and its chief operating officer, Peter DeCoster, are expected to plead guilty to introducing adulterated food into interstate commerce, a misdemeanor.

The DeCosters face sentences ranging from probation to one year in jail, according to plea agreements filed Monday by federal prosecutors. Jack DeCoster, 79, of Turner, Maine, and his 50-year-old son Peter, of Clarion, Iowa, have agreed to pay $100,000 fines each.

U.S. District Judge Mark Bennett must approve the plea agreements and sentence the DeCosters who, along with Quality Egg, could also be ordered to pay restitution to victims.

Bill Marler, an attorney who represents dozens of the salmonella victims, said the $6.8 million fine is the largest he’s heard of in 20 years of practicing food safety law. The fines and potential jail time send “a very strong message to companies that food safety is paramount,” he said.

The government blamed Quality Egg’s tainted eggs for a 2010 salmonella outbreak that sickened thousands and led to the unprecedented recall of 550 million eggs. The DeCosters have since left the egg industry.

Investigators found no evidence that the DeCosters knew they were selling tainted products in 2010. But as corporate officers, they were in position to “detect, prevent and correct the sale of the contaminated eggs” had they known, the plea agreements say.

The investigation also found no evidence that the DeCosters knew that Quality Egg deliberately mislabeled eggs from 2006 to 2010 to fool regulators and consumers about their age to circumvent laws in California, Arizona and elsewhere that require eggs to be sold within a month or less of their processing dates.