The U.S. Food and Drug Administration (FDA) yesterday authorized New Hampton-based Hillandale Farms of Iowa Inc. to begin shipping eggs from three of its producers.

Hillandale Farms was one of two companies that recalled 550 million eggs in August amid a salmonella outbreak.

The FDA extensively tested three Hillandale houses and found no evidence of salmonella contamination. Four other houses overseen by Hillandale are undergoing further testing.

The FDA notified the other company involved, Galt-based Wright County Egg Production, to take “prompt and aggressive actions” to eliminate salmonella contamination or risk being shut down.