Biscuits from Fermented Roasted Buckwheat Flour - Phenolics Profile and Bioaccessible Angiotensin Converting Enzyme Inhibitory Activity

The bioaccessible angiotensin converting enzyme (ACE) inhibitory activity of biscuits formulated from roasted common buckwheat flour after fermentation by select bacteria was studied. The same content of total phenolic compounds was found in fermented flour and in biscuits obtained from them. Generally, fermentation of flour did not changes the ACE inhibitory activity, whereas baking process significantly increased the ACE inhibitory activity of examined products. The potential bioaccessible ACE inhibitory activity from biscuits was very high. Phenolic acids such as protocatechuic, vanillic and syringic acids as well as flavonoids: kaempferol and epicatechin in the digested buckwheat biscuits have the highest impact on ACE inhibitory activity. A high significant correlations were found between IC₅₀ and total phenolic compounds of fermented flours, biscuits before and after digestion. The data obtained in this study closely associates phenolic compounds with ACE inhibitory activity.