Reduction of deoxynivalenol during barley steeping in malting using plasma activated water and the determination of major degradation products

Deoxynivalenol (DON) is one of the most prevalent mycotoxins contaminating cereal grains such as barley, causing yield loss and health concerns for consumers. Cold plasma treatment is an emerging method and has the ability to degrade DON. The aim of this study was to investigate the application of plasma activated water (PAW) in barley steeping to reduce the concentration of DON in naturally infected barley (NIB). The quality features of the barley malt steeped in PAW were then assessed. Besides, the major degradation products of DON after cold plasma treatment were determined. A 30-min PAW treatment of NIB followed by steeping resulted in significant reduction of DON compared to control. The beta-amylase activity in PAW treated barley malt were higher compared to control. The significant reduction in DON in NIB without influencing the germination and quality parameters of barley malt indicates the potential application of PAW for barley steeping. The high-performance liquid chromatography ultraviolet mass spectrometry results indicated several DON degradation products after cold plasma treatment. The structures of the major DON degradation products suggested oxidation as the main degradation mechanism during cold plasma treatment.