The team scanned a cast of Bach's skull to build this picture

It is believed that only one portrait he sat for still exists.

However, forensic artists at the university built up a picture of his appearance using a bronze cast of his skull and documents from the time.

The face will go on display at the Bachhaus museum in Bach's hometown of Eisenach next month.

'Accurate picture'

Dr Caroline Wilkinson, from the Centre for Forensic and Medical Art, explained how they worked out the composer's features.

"We carried out a laser scan of the skull which allowed us to recreate the musculature and skin of the face on our computer system," she said.

"By assessing the bone structure we can determine facial morphology and produce an accurate picture of his facial appearance."

The team then used an existing portrait of Bach, and documents which described how his eye problems caused swollen eyelids, to start texturing the face.

Dr Wilkinson said: "This is really the most complete face that can be built from the available reliable information.

"As far as we can ascertain, this is how Bach would have looked."

Director of the Bachhaus Eisenach, Joerg Hansen, said: "People are interested in what he looked like, they have busts of Bach on the piano.

The traditional image of Johann Sebastian Bach

"It's always this old man with a wig type of image we have in mind when we hear the name or think of how he looked.

"I think it is interesting for fans to have something else, a real person."

Mr Hansen told the BBC Scotland news website that some people had suggested the face looks Scottish, although he believes it has the features of those you meet in Eisenach.

"It's very dynamic, as if he's going to come up with something. That is, I think, quite fitting," he said.

"He has this furrow over the nose, which makes him look, maybe, a bit angry, or easy to anger.

"Caroline Wilkinson actually explained to me that had nothing to do with the character at all, it's determined by the skull.

"If you have that type of skull you have to furrow over the nose.

"But I also think he looks interesting."