Pasteurisation to protect against AI and ND

Agricultural Research Service scientists have discovered that the same pasteurisation temperatures and times used to ensure eggs products are free of salmonella can also kill AI and ND viruses.

David Swayne, laboratory director of the Southeast Poultry Research Laboratory found that AI and ND viruses could be destroyed by pasteurisation. Pasteurisation is a short-term, low-heat process used to kill bacteria in milk, egg products and other food items without changing the cooking properties or flavour of the food.

Swayne established that heat inactivation occurred between 55 and 63 degrees Celsius, although the time needed to inactivate the viruses depended on virus strain and egg product.

“While there are studies indicating that these viruses can be transmitted to birds by ingestion, there are no definitive results showing the same is true for humans. But inactivating the viruses in egg products will preclude possible transmission to humans.”

Swayne artificially infected four commercial egg products with AI and ND viruses and then subjected them to standard, recommended pasteurisation temperatures and times, which proved to kill the viruses.

“This study is important because we were able to determine inactivation curves for various temperatures and times for future reference,” says Swayne.

This research shows that egg products potentially infected with AI and ND viruses can be pasteurised and then safely exported and used for food consumption, thereby increasing international trade and improving food safety.