Nestle, the world's largest packaged food group, said it had made a scientific breakthrough that has the potential to reduce sugar in its confectionary products by up to 40%. 

"Our scientists have discovered a completely new way to use a traditional, natural ingredient," the company's chief technology officer, Stefan Catsicas, said in a statement last night. 

The announcement comes as a global obesity epidemic ramps up pressure on food makers to make their products healthier. 

Using only natural ingredients, Nestle said its researchers had found a way to structure sugar differently, so that less sugar can be used in chocolate with no difference to taste. 

The maker of Kitkat and Aero bars said it was patenting its findings and would begin to use the faster-dissolving sugar across a range of its confectionery products from 2018.