Influence of pulsed electric field treatment on the fate of Fusarium and Alternaria mycotoxins present in malting barley

Mycotoxin contamination of cereals is a global problem. Different decontamination technologies are in use today, from simple non-destructive ones such as sorting and sieving, to more sophisticated physical methods exploiting irradiation, ultrasound, cold plasma or a pulsed electric field (PEF). The current study focuses on characterizing the effect of PEF on mycotoxins present on malting barley. The degradation potential, as well as changed extractability into the electrolyte (water) after PEF treatment was assessed for 16 common and emerging Fusarium and Alternaria mycotoxins, using ultra-high performance liquid chromatography coupled with high-resolution tandem mass spectrometry. The presence of degradation/transformation products was screened for in the samples after in silico prediction. The overall PEF-induced reduction in trichothecenes, zearalenone, enniatins, beauvericin, and tentoxin, calculated based on the dry matter of barley, was up to 31, 48, 84, 36 and 46%, respectively. For the majority of mycotoxins, decreases were also observed in water, whereas for type A trichothecenes, zearalenone, enniatins, and beauvericin, increases up to 130, 123, 629 and 192% occurred, probably associated with facilitated extraction from the matrix (100% = mycotoxins rinsed into water independent of PEF treatment). The degradation/transformation products of mycotoxins were mostly the result of hydrolysis, elimination and/or oxidation.