Abstract
Different cheese samples produced in Latvia (eight) and Belgium (13) were analysed for their sterigmatocystin (STC) content. Only two (9.5%) of the samples were positive for STC with concentration levels of 1.23 and 0.52 µg kg−1, respectively. Five (24%) samples contained STC above the limit of detection (0.03 µg kg−1) but below the limit of quantification (0.1 µg kg−1), A sensitive liquid chromatography-electrospray positive ionisation-tandem mass spectrometry (LC-MS/MS) method, which was previously developed for the analysis of STC in grains, was modified and applied to the analysis of STC in cheese. This method involved sample extraction with acetonitrile–water (90 : 10, v/v), defatting with n-hexane, solid-phase extraction, separation on a reversed-phase C18 column, and STC detection by LC-MS/MS.
Acknowledgements
The study was financially supported by the ESF, National Programme: ‘Support in Doctoral and Postdoctoral Programme Realization and Investigation’ (Contract No. VPD1/ESF/PIAA/04/NP/3.2.3.1./0001/0005/0067) and the European Commission in a ERASMUS lifelong learning agreement within the framework of ERASMUS subprogramme and by Latvian government for ERASMUS mobility programme realization (Contract No. 29–07/08).