Inhibition Of Fusarium Graminearum In Wheat By ClO₂ And Essential Oil Treatment And Its Effect On Flour Quality

Wheat head blight caused by Fusarium graminearum will cause a large area of grain yield reduction,seriously affect the quality and safety of grain,and cause serious economic losses.At the same time,deoxynivalenol(DON)toxin,a secondary metabolite produced by the bacteria during the infiltration process,will accumulate in the grain,which will not only reduce the quality of wheat,but also cause harm to the health of humans and animals after being eaten..Using appropriate methods to inhibit the further reproduction of Fusarium graminearum in the infected grain is an effective way to prevent Fusarium graminearum from harming food quality and safety.The bacteriostatic effect and mechanism of ClO₂ water solution,clove essential oil and cinnamon essential oil against Fusarium graminearum were investigated.Based on this,the antibacterial effect and the effect on wheat flour quality of Fusarium graminearum infected wheat were further investigated.The main conclusions were as follows:(1)ClO₂ aqueous solution had significant inhibitory effect on Fusarium graminearum.Through Oxford cup method,it was found that Fusarium graminearum could avoid the growth of Oxford cup soaked with ClO₂ aqueous solution,ClO₂ aqueous solution had antagonistic effect on Fusarium graminearum;through the inhibition experiment on mycelial growth,the IC₅₀ of ClO₂ aqueous solution was 27 mg/L.(2)the inhibitory effect of cinnamon essential oil and clove essential oil on Fusarium graminearum was investigated by fumigation.The results showed that cinnamon essential oil and clove essential oil had inhibitory effects on Fusarium graminearum.The inhibitory effect of clove essential oil was lower than that of cinnamon essential oil at low concentration(20?L/Lair),but with the increase of concentration,the inhibitory effect of cinnamon essential oil was significantly higher than that of cinnamon essential oil.The IC₅₀ value of clove essential oil and cinnamon essential oil was 58?L/Lair and 66?L/Lair respectively by calculating the inhibition rate on the inhibition of mycelial growth.(3)Through the determination of ergosterol,scanning electron microscope observation and Fourier transform infrared analysis of mycelium,it was found that ClO₂ and essential oil had different degrees of damage to the cell structure of Fusarium graminearum,which indicated that the two treatment methods had effects on the cell structure of Fusarium graminearum.ClO₂ aqueous solution mainly destroyed cell membrane and exuded the contents,resulting in inactivation of bacteria.The effect of clove essential oil and cinnamon essential oil on mycelia was different.High concentration clove essential oil could destroy cell structure,while cinnamon essential oil mainly caused the development of bacteria.(4)Wheat was infected with Fusarium graminearum and treated with ClO₂ solution could inhibit the growth of Fusarium graminearum better,but the effect of increasing concentration only slowed down the germination time of Fusarium graminearum and had no significant effect on the final germination rate.After adorable wheat adorable oil,the hyphae of wheat grains were less and a bacteriostatic circle formed around them,indicating that Fusarium graminearum was not killed and spore escaped from wheat.It continued to grow and reproduce on the plate.(5)comparison showed that the inhibition effect of ClO₂ aqueous solution and clove essential oil on wheat was not as good as that of the direct treatment of Fusarium graminearum.The combination of ClO₂ solution and clove essential oil treatment showed that the inhibition effect was more significant,and the suitable combined treatment conditions were optimized to soak 20min in the ClO₂ solution of 70mg/L concentration,with a concentration of 80?L/Lair clove essential oil fumigated 48h.Under these conditions,the accumulation of DON toxin was 54.44 and 48.89 percentage points lower than that of ClO₂water solution and clove essential oil respectively,indicating that combined treatment of ClO₂aqueous solution and clove essential oil could better prevent DON toxin production.(6)the quality of wheat flour treated with ClO₂ solution and clove essential oil was investigated under optimized conditions.The results showed that there was no significant change in whiteness,fatty acid and protein composition after storage for one month.The volatile components of the flour from GC-MS were found to be effective in reducing acid,aldehydes and esters produced by Fusarium graminearum.And other volatile substances to improve the flavor of flour.At the same time,it was also detected that the related components of eugenol essential oil such as eugenol were preserved in flour,and the residual content decreased gradually with the increase of storage time,and the effect on flavor was gradually reduced.