Analytical method for detecting multimycotoxins in roasted coffee samples using liquid chromatography-tandem mass spectrometry

Abstract

Mycotoxins are natural toxins that consist of secondary metabolites produced by fungal species of Aspergillus, Fusarium, and Penicillium. The present work aimed to validate the analytical method for detecting multimycotoxins (aflatoxin B1, B2, G1, G2, fumonisin B1, B2, ochratoxin A, and zearalenone) in roasted coffee samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Eight stable 13C isotope-labelled internal standards were used for quantification, and an immunoaffinity column (IAC) was used for sample pre-treatment to eliminate interferences. Calibration curves showed good fitness (R2 > 0.995) for all mycotoxins tested. The method detection limit (MDL) and method quantification limit (MQL) for eight mycotoxins were in the range of 0.002 - 0.2 and 0.005 - 0.5 ng/g, respectively. The recoveries ranged from 98.2 to 111% at three concentrations. The coefficients of variation (CVs) ranged from 1.2 to 14% intraday, and 1.4 to 13% interday. These results were within the acceptable range of the Codex Alimentarius Commission (CAC), thus indicating that the validated method could be suitable for multimycotoxin detection in roasted coffee samples.