Influence of interstitial carbon dioxide on deoxynivalenol accumulation in stored wheat under varying Fusarium treatments and airtight storage conditions

BACKGROUND Temperature and moisture content are recognized as the main factors responsible for mycotoxin production in stored grain, while the role of gaseous environment, particularly interstitial CO 2, remains unexplored. This study investigated the relationship between interstitial CO 2 concentration (generated metabolically in air spaces between grain kernels) and deoxynivalenol (DON) production in stored wheat under varying moisture contents (13%, 15%, 17%, 20%, or 23%), Fusarium treatments (naturally infected, Fusarium ‐inoculated, disinfected, or disinfected + Fusarium ‐inoculated), and airtight durations (1, 3, 6, or 12 days). RESULTS Moisture was the dominant factor affecting both CO 2 and DON production, explaining most of the observed variance. Fusarium inoculation significantly increased interstitial CO 2 concentration, daily CO 2 production (generated interstitially depending on airtight duration), and accumulated CO 2 production (accumulated interstitially until the end of the storage period). Airtight duration significantly affected CO 2 production and influenced DON concentrations. A significant positive correlation ( r = 0.87, P < 0.001) between interstitial CO 2 and log 10 ‐transformed DON concentration was obtained. CONCLUSION Wheat with <20% interstitial CO 2 concentration remained below safety thresholds for DON concentration, and >30% interstitial CO 2 was found in 60% of DON‐contaminated samples, suggesting a cut‐off for safe storage and that monitoring of interstitial CO 2 concentration during grain storage may provide a helpful indication of the risk of grain quality loss. These findings offer a practical approach to minimizing DON accumulation in stored wheat.