High-performance liquid chromatographic determination of the mycotoxins patulin, penicillic acid, zearalenone and sterigmatocystin in artificially contaminated cocoa beans

A high-performance liquid chromatographic (HPLC) method has been developed to allow the determination of patulin, penicillic acid, sterigmatocystin and zearalenone in samples of cocoa beans. When this method is combined with a method that was reported earlier for the determination of ochratoxin A [W. J. Hurst and R. A. Martin, Jr., J. Chromatogr., 265 (1983) 353], it allows for the determination of five mycotoxins. Samples were extracted with an acidic acetonitrile solution, partitioned with hexane to remove fat interferences and then partitioned with chloroform to remove the toxin containing fraction. Interferences were removed by the use of a bonded phase column followed by the final HPLC determination step, which uses a cyano column with a hexane-1-propanol-acetic acid mobile phase with dual channel UV detection at 245 and 280 nm. The method exhibits good linearity, accuracy and precision.