A recipe for unmeltable chocolate has been invented by pupils in the south Wales valleys as a special treat for British troops serving in Iraq.
The pupils spent more than a year making the heat-resistant chocolate
Four pupils at Afon Taf High School in Ynysowen, near Merthyr Tydfil, heard that soldiers in the hot Middle East were fed up of chocolate treats sent out by their families melting before they could be eaten.
So the Year 10 classmates set about making a recipe for heat-resistant chocolate by adding glycerine to the mix.
Their efforts in the kitchen have won them an award from a national science competition.
The pupils spent more than a year researching and testing the product in the lab during their lunch breaks, before finally coming up with the perfect recipe for unmeltable chocolate.
Louise Treen, Sarah Moore, Bethan England, Sarah Morris, and Samantha Sear are now working on turning the unmeltable chocolate into bars before they send it over to the troops.
"They have worked on the project for over a year during their lunchbreaks," said the girls' teacher Carolyn Scott.
"There have been all sorts of taste testing and they have become very popular among the other pupils in the school.
"Initially, the girls were going to do a project investigating chocolate in the diet.
"But that all changed after they heard about the soldiers in Iraq missing chocolate because it melted before they got it."
The girls spent months writing to different chocolate manufacturers and looking up recipes on the internet because they discovered the magic ingredient was glycerine.
By adding glycerine, the chocolate does not melt until it is in the mouth where the glycerine dissolves and the chocolate softens.
But despite winning the Creativity in Science and Technology competition at the Royal Society, the unmeltable treat will not be stocked on shelves because of EU regulations.
The product cannot be classified as chocolate because it does not have the required amount of cocoa butter.
"The girls are still trying to perfect everything and are desperately trying to get someone to make the chocolate," said Carolyn Scott.