Effect of liquid-state fermentation on the antioxidant and functional properties of raw and roasted buckwheat flours

The influence of liquid-state fermentation (LSF) by selected lactic acid bacteria (LAB) and Rhizopus oligosporus fungi on the content of rutin and total phenolic compounds (TPC), antioxidant capacity measured by ABTS test, FRAP assay and photochemiluminescence technique, and the inhibitory activity against formation of fluorescent advanced glycation end-products (AGEs) in vitro of raw and roasted buckwheat flours was studied. LSF caused a slight, specific LAB-dependent increase in TPC and a decrease in rutin content. Fermented raw buckwheat flours contained higher amounts of rutin and TPC with one exception when the highest increase in TPC was noted in roasted flour fermented by fungi. A LAB-dependent difference in the antioxidant capacity of buckwheat flours was noted while the inhibitory activity of fermented flours against AGEs formation was generally reduced. It can be concluded that LSF with selected LAB and fungi may improve the antioxidant and functional properties of buckwheat flours.