McDonald's, Target Dump Egg Supplier After Investigation

More than a half-billion eggs had to be destroyed and the episode produced a nationwide health scare over the safety of eggs. That outbreak did not affect any McDonald's products, the company said.

Salmonella in eggs is easily killed when both the white and the yolk are cooked thoroughly enough to be hard.

Many of those sickened last year ate custard at a California catering hall that had eggs from Wright County Eggs.

Federal authorities promised stepped up inspections and enforcement, and FDA officials said this week's action against Sparboe Farms was part of that effort.

McDonald's says its customers should have no health concerns because all of it eggs are thoroughly cooked before being sold.

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"This is not a food safety issue for our menu items," McDonald's said in its statement. "We can assure our customers that eggs in our entire supply chain meet McDonald's high standards for quality and safety."

As to the allegations of animal cruelty, a spokesperson said the behavior seen on videos provided by 20/20 was "disturbing and completely unacceptable."

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