AN investigation is underway at a district contractor to discover if out-of-date chocolate meant for pig feed was used by confectionery giant Cadbury.

The Birmingham-based firm ordered the probe after claims that R and JB Higgins, of Chaddesley Corbett, had melted down out-of-date chocolate and supplied it back to the company for use in some of its brands including Dairy Milk and Creme Eggs.

The Bournville factory has stopped using chocolate processed by the contractor until the results of the investigation are known - but it insisted it had "total confidence" in its supplier of 15 years.

The Grove Farm-based company denied the claims, which were made in a national newspaper on Sunday, and said the public had "nothing to fear".

Cadbury spokesman Richard Frost said: "I would be amazed if the allegations were true as there is no motive for doing this.

"It simply does not make sense."

The contractor is supposed to sort the bars into those which are perfectly edible but imperfect in some way - where the chocolate can be melted down and re-used - and those which are past their 'best before' or 'sell-by' date.

These are sold to farmers for use in pig feed.

The allegations claim workers, who are paid a piece-rate for the amount of chocolate recycled, were operating a fiddle by adding chocolate from the pig feed pile.

Roger Higgins, who runs R and JB Higgins with his wife and son, said his firm had a sound working relationship with Cadbury.

He added: "We have worked closely together for a very long time and as a customer they insist on very high standards.

"A number of allegations have been made and investigators arrived here first thing on Monday morning to begin their work."