Compressed air could soon be used to label food products with a spray-on ‘DNA barcode’ so that, if that food is later found to be tainted, it can be traced immediately back to its source with a high degree of accuracy.

The Lawrence Livermore National Laboratory in the US has developed DNATrax, a spray-on substance that has been categorised as a safe food additive, and which contains unique DNA identifiers to allow food to be traced back to the place of production, and even which individual produced it or picked it.

It is a previously unexpected use for a technology that was originally developed as a way to track the flow of air both indoors and outdoors.

George Farquar, a physical chemist at the laboratory who led the development team, says: “One of the unexpected capabilities from DNATrax was being able to apply it to food products.

“You can spray it on food products in the field to identify and track the source of the food.”

Indeed, while compressed air may be used to spray DNATrax on to food items at the point of production, the technology could itself be used in compressed air installations, helping to identify the movement of the air through the system – just as it was originally intended to do.