Method for detecting migration quantity of PGA oligomer in food packaging material

The invention provides a method for detecting a migrated PGA oligomer of a food packaging material, which comprises the following steps: 1) dissolving a sample in an organic solvent, sealing and standing, and adding a precipitator to separate PGA to obtain a sample solution containing the oligomer; (2) detecting the sample solution by using UPLC-QTOF-MS, recording the appearance time, and determining the variety according to the mass-to-charge ratio, so as to establish a database; (3) mixing a to-be-detected sample with a food simulant, sealing, standing at constant temperature, and taking out the to-be-detected sample to obtain a to-be-detected solution; and 4) adding an internal standard substance, detecting the to-be-detected solution added with the internal standard substance by using UPLC-QTOF-MS, recording the appearance time of each component, comparing with the database obtained in the step 2), determining the type of the oligomer according to the appearance time, and comparing with the integral area