The origins of this song are lost in our long long history but you mentioned tuckerbag. Perhaps it was written with a juvenile haggis in mind.
Once a jolly swagman camped by a billabong,
Under the shade of a coolibah tree,
And he sang as he watched and waited till his billy boiled,
"Who'll come a-micing Matilda with me?
mincing Matilda, mincing Matilda,
Who'll come a-mincing Matilda with me?"
And he sang as he watched and waited till his billy boiled,
"Who'll come a-mincing Matilda with me?"
.....................
And he sang as he shoved that jumbuck in his tucker-bag,
"You'll come a-mincing Matilda with me."
Here you can see evidence that swagman really did hunt mince as evidenced by their state of the art tuckerbags.