Selective effect of propionates and water activity on maize mycoflora and impact on fumonisin B1 accumulation
2000
Marin, S. | Magan, N. | Abellana, M. | Canela, R. | Ramos, A.J. | Sanchis, V.
The effect of a commercial mixture of propionates at two different doses (0.05% and 0.1%) on fungal spoilage of natural maize stored at 0.85, 0.90 and 0.95 water activity (aw) was investigated. Parallel treatments with added inoculum of Fusarium Liseola section isolates (Fusarium moniliforme and F. proliferatum) were carried out in order to determine the effect of fungal interactions on the development of fumonsin-producers on maize in relation to preservative efficacy. Fungal colonisation of grain was measured as fungal counts (CFUs g-1 maize). In general, no differences were found between inoculated and uninoculated samples. Besides the selective effect of (aw) on maize mycoflora, it was demonstrated that most genera which colonise maize remained unaffected by the preservative concentrations applied. However, Penicillium populations (CFUs g-1 maize) counts decreased significantly. As they represent a major component of the total fungal counts, an overall control of total mycoflora was observed. Furthermore, there was a significant statistical interaction between preservative and (aw) levels, with the preservative activity enhanced at low (aw). The concentrations of fumonisin B1 were unaffected by treatment with no significant differences in concentrations found. This suggests that the natural mycoflora of maize may act as in inhibitor of Fusarium development, and consequently of fumonisin biosynthesis.
显示更多 [+] 显示较少 [-]