Antonio Lombatti said the false shrouds circulated in the Middle Ages, but most of them were later destroyed.
He said the Turin Shroud itself - showing an image of a bearded man and venerated for centuries as Christ's burial cloth - appears to have originated in Turkey some 1,300 years after the Crucifixion.

The Turin Shroud was believed to have covered Jesus, but a leading Church historian says it is one of many produced over a thousand years after his death.
'Most of them were destroyed during the French Revolution. Some had images, others had blood-like stains, and others were completely white.'
The Turin Shroud is a linen cloth, about 14ft by 4ft, bearing a front and back view of the image of a bearded, naked man who appears to have been stabbed or tortured. Ever since the detail on the cloth was revealed by negative photography in the late 19th century it has attracted thousands of pilgrims to the Cathedral of St John the Baptist in Turin.
In a research paper to be published this month in the scholarly journal Studi Medievali, Lombatti says the shroud was most likely given to French knight Geoffroy de Charny as a memento from a crusade to Smyrna, Turkey, in 1346. The de Charny family are the first recorded owners of the shroud.

The image has bewitched believers and skeptics alike since the negative image, right, was revealed in the late 19th century.
The Catholic Church has never officially commented on the shroud's authenticity, but has made samples available to scientists for testing.
In 2009 a Vatican researcher said she had found the words 'Jesus Nazarene' on the cloth, while two years later Italian government researchers claimed the image of a man had been caused by a supernatural 'flash of light'.
But carbon tests carried out in Oxford in 1988 firmly dated the material to 1260-1390.
...that the origin of the fake burial cloths of Jesus is shrouded in mystery.
(I just can't help it, folks! Some things fairly beg to be ridiculed.)
Moreover, if all of the fake slivers of the "True Cross" were to be gathered together from the altars of Catholic churches around the world, one could probably build at least a small dingy.
There are several fake foreskins of Jesus floating around, too.