"It seems too good to be true, if the deal is just too good, that's a warning sign," said Doug Karas of the Food and Drug Administration.
Karas says food fraud works two ways: First, by cheating the weight of a product, and second, by substituting a lower quality item.
The most well-known counterfeit products are olive oil, honey and seafood.
"When a fish is filleted, it's very difficult to tell one fish from another," Karas said.
The National Seafood Inspection Laboratory determined 34 percent of all fish sold in U.S. wasn't the species that it was labeled as. Only two percent of imported fish are inspected by the FDA.
"You don't know what's in there. You don't know what you're eating," said David Shaw, Immigrations Customs Enforcement assistant special agent.
Shaw tracks down the food before it gets to consumers. Agents stopped a load of cheese at a warehouse in Miami.
Shaw said they tell the FDA the container has bread, but when agents looked inside the container, it was bread and cheese.
"This cheese had staph, it had E. coli, it had everything you could think of," Shaw said.
The FDA inspects only one percent of the 10 million products shipped into the country annually. Shaw says that's why food fraud is a lucrative way for organized crime to make money.
"The penalties are not there yet. We have not seen anyone get more than nine months of home confinement," Shaw said.
In Operation Rotten Tomato, SK Foods was investigated for selling moldy, expired tomato derivatives to Kraft and Heinz as an expensive form of paste.
In other cases, sheep's milk cheese was actually the product of cow's milk, and honey was diluted with corn syrup.
"There's a near infinite number of fraudsters, and there's a near infinite number of types of fraud," said Dr. John Spink, who helped to create the first anti-counterfeiting and product protection program at Michigan State University.
Spink fears if we don't get in control of it now, lives will be put in jeopardy. We've already seen what can happen when 3,600 pets died because melamine.
"Melamine was put in pet food because that product made it look like it had more protein in it," Spink said.
Melamine is 66 percent nitrogen and is used to make plastics.
"If something bad gets into the system, it can move and impact so many people so quickly," Spink said.
With 48 million contracting food borne illness every year, experts say food fraud is far more than an economic risk.
If you suspect food fraud, report it to the FDA by calling the hotline at (888)SAFE-FOOD.
