Retention of deoxynivalenol and its derivatives during storage of wheat grain and flour

• DON, 15-AcDON and 3-AcDON levels in wheat grain all decreased during 180-day storage.
• DON in wheat flour increased and 15-AcDON and 3-AcDON decreased after 180-day storage.
• D3G levels in some wheat grain and flour samples increased after 180-day storage.
• Conversion of DON and its derivatives may occur during wheat grain and flour storage.

Fate of deoxynivalenol (DON) and its derivatives—deoxynivalenol-3-glucoside (D3G), 15-acetyldeoxynivalenol (15-AcDON) and 3-acetyldeoxynivalenol (3-AcDON) during six-month storage of wheat grain and flour was investigated. Wheat grain and flour polluted by DON, D3G, 15-AcDON and 3-AcDON were packaged in polyethylene bags, kraft paper bags and cloth bags, and stored at room temperature and 4–6 °C, and mycotoxin levels were analyzed by UPLC-MS/MS after storing for 30, 90 and 180 days. Levels of DON, 15-AcDON and 3-AcDON in wheat grain showed a generally decrease during the storage duration, and DON concentrations averagely decreased by 40–50%. An obviously increase of DON (more than 70%) and decrease of 15-AcDON and 3-AcDON were observed after storage in wheat flour. There were no significant differences of D3G levels in most of wheat grain and wheat flour samples after storage, but some increased dramatically with retention level up to 240%. The results suggested conversion of DON and its derivatives may occur during wheat grain and flour storage.