Perth Royal Show organisers found themselves between a rock and a hard place on Tuesday after a prominent showbag with out-of-date candy was sold at the popular event.

Padbury grandfather Maurice Rose has accused Perth confectionary maker Roc Candy of deliberately selling old candy in its showbags, in a story first revealed on Radio 6PR Breakfast's Rumour File.

The Roc Candy sugar free showbag has five lolly packets - all best before December 2015. Credit:Maurice Rose

Mr Rose, who helped pay for his grandchildren to attend the show last Saturday, was overjoyed when they bought him back the Roc Candy Sugar Free showbag as a thank you gesture ... until he bit into it.

"I took a bite of one of them and expected it to taste better, so I looked at the back of the packet to check the date," Mr Rose said.