SAO biscuits are Australian savory biscuits or crackers which have been trademarked by Arnott’s since 1904. According to the producer, these biscuits are made from seven layers of flaky pastry, and they have a distinctive light and bubbly texture.

Many generations of Australians are fond of these biscuits because of the small holes on their surface. When buttered and squeezed together, two biscuits produce ‘worms’ of butter which start to emerge from the tiny holes. The same effect is achieved if the filling includes Vegemite.

The name of the biscuits is still a mystery, but most people believe it refers to a Salvation Army Officer.