Development of a Mass Spectrometry-Based Quantitative Method for Two Isoallergens of Celery Allergen Api g 1 in Fresh and Processed Celery.

Celery can trigger severe food allergies and is often associated with birch pollen allergies. Although celery must be declared on food labeling in the European Union, few studies have investigated its allergen content. This study introduces a simultaneous quantitative method to determine the actual content of two isoallergens of Api g 1 in fresh and processed celery, by using mass spectrometry. Excellent analytical performance was achieved, with limits of detection and quantification of 0.06 μg/g and 0.13 μg/g, respectively, with recovery range of 95.0-80.4%, and intra- and inter-day precision relative standard deviation values of 8.0-2.0% and 11.0-5.1%, respectively. Furthermore, the calculated content of the total Api g 1 isoallergens in raw celery ranged from 3.24-91.25 μg/g. Therefore, this method is useful for providing reliable data to the food industry and people with food allergy.