Researchers used a technique called direct infusion mass spectrometry to analyse the ink and paper of both authenticated and forged Burns’ manuscripts.
They then developed a classification system which accurately distinguishes Burns’ real handwriting from the fakes.
They tested 12 documents - three real Burns documents from different periods of the bard’s life, and nine fakes from the 1890s by notorious forger Alexander Smith.
The technique lifts ink from the paper surface in a way that does not visibly damage the original material and can be done outside the laboratory, enabling widespread use.
Researchers also found Burns was mixing an ink made from carbonised ivory, sulphuric acid and stale beer with another ink made with wine to achieve writing lustre and consistency on some documents.
Glasgow University’s Dr Karl Burgess, who worked on the study, said: “Through this technique we now know some things about Burns that we never knew before.
“However we’re particularly excited about that fact that we have a new way of providing more evidence for a fake or a real manuscript if one turns up, and we have a technique that we can apply to any manuscript to gain more information about it.
“The simplicity of the sample preparation method we used means that the sampling can be easily performed at the site where the manuscripts are stored, which in turn could make it an ideal technique for auction houses to confirm authenticity.
“In future, we’d like to analyse as many historical documents we can, so that we can begin to build a database of inks and manuscripts.”
His university colleague Professor Gerard Carruthers added: “In terms of Robert Burns there has been a huge historic industry in forgery and fakery, and he is not alone in this.
“It is very exciting that we’re creating an authenticity tool that will have wide implications for scholars, libraries, archives, auction houses and collectors.”
The study is published in Scientific Reports.