Health authorities are testing more samples from two Adelaide bakeries associated with a salmonella outbreak linked to custard-filled pastries.

At least 60 people have fallen ill, nearly half of them needing to be admitted to hospital.

SA Health's investigation has linked the infections to Vili's custard-filled berliner buns and St George Cakes and Gelati's custard-filled cannolis and eclairs.

Kevin Buckett from SA Health says they expect more test results later in the week.

"We have taken more samples from the manufacturing plants," he said.

"We're continuing to interview the 60 or so people that were notified to us last week and obviously the more we interview the better chance we have to get a good track on what common foods people have eaten."