The aim of the present work was to assess the influence of the baking process on the fumonisin content in glutenfree
bread. The dough was made using two methods: without sourdough and with sourdough. Fumonisins were determined
using high-performance liquid chromatography with ion-trap mass spectrometry. This study showed that the bread baking
process caused a statistically significant drop in the mean concentration of free fumonisins: the reduction levels were 30 and 32%
for the direct and sourdough-based methods, respectively. The lower reduction after baking was observed for hidden fumonisins:
19 and 10%, respectively. The presence of some compounds (such as proteins or starch) capable of stabilizing fumonisins during
the baking process might be responsible for the observed increase in the hidden-to-free ratio from an initial 0.72 in flour to 0.83
in bread made from sourdough and to 0.95 in sourdough-free bread.