He repeated the display a week later, when he met with a representative from the onion industry in Parliament House, reportedly taking a few bites from another brown onion and describing it as "tasty".

A biting taste: spring onions. Credit:Jennifer Soo

But that wasn't the first time the Prime Minister has performed the odd act, according to archival footage unearthed on Wednesday, which shows Mr Abbott has been sampling raw onions for at least four years.

In a short video posted by ABC News to video platform Vine, Mr Abbott - who was then Opposition Leader - can be seen biting gamely into the raw produce as a farmer and colleagues watch on.

The object of his culinary curiosity, tentatively described by the ABC as "another member of the onion family", appears to be a spring onion.