G01023: Development of sensitive and robust mass spectrometric methods for detection of GM material in food ingredients

Study Duration: September 2003 to August 2005

Contractor: Royal Holloway, University of London

Real-time polymerase chain reaction (PCR) amplification is regarded as the ‘method of choice’ for quantification of genetically modified (GM) material in food as there are currently no reliable alternatives. This project looked at a method for the detection of GM proteins that could be used for the quantification of GM material in food matrices.

The aim was to develop a robust, high throughput method for the detection of GM proteins in food products using mass spectrometry (MS).

The method was able to reach the level of sensitivity required by current legislation (0.9%) and could be improved to detect GM material at 0.1%. The method was also able to detect GM material in real food matrices such as sausages and bread that had been spiked with GM protein. A method was successfully developed to quantify the amount of GM protein present. This method proved to be reproducible and correlated well with the theoretical amount of GM protein present. The method has been patented by Royal Holloway, University of London (RHUL) and could be used by industry when it is desirable to detect the presence of low levels of GM material.

The GM food and feed regulation (1829/2003) requires the labelling of food products containing genetically modified organisms (GMOs) unless the GMO content is <0.9% and is due to adventitious and unintended presence. Member States are required to put in place control measures to enforce the regulations. Current techniques available for the detection of DNA or protein are PCR and ELISA (enzyme-linked immunosorbent assay), respectively.

This project explored the applicability of MS to the identification of the GM proteins found in common GM crops such as, soya, maize and tomato. It was also designed to establish if the technique would be sensitive enough to detect the GM proteins at the levels required by the legislation (0.9%).

The contractor approached the study by using a combination of traditional biochemical techniques for protein purification with state of the art MS to detect and identify the GM proteins in soya, maize and tomato. Once this was achieved, foods were spiked with different levels of GM protein and then tested using MS. The level of GM protein in these samples was also quantified to determine the amounts of GM proteins in the foods. The limits of sensitivity were also determined.

This study has shown that MS can be used to detect GM crops such as soya, maize and tomato in foods such as sausages and bread more accurately than existing techniques; and that the limits of detection are lower than the threshold set by EU regulations.