Effect of flavonoid structures on Maillard reaction product formation in cookies

Abstract Flavonoid structure plays a crucial role in the inhibition of Maillard reaction product formation during baking and might impact sensory properties of final products. The goal of this study was to assess the effect of flavonoids common in whole grains on Maillard reaction product (MRP) formation in cookies -a low-moisture chemically leavened model system. Four flavonoids – luteolin, catechin, eriodictyol, and taxifolin—were added at 0.1% in cookie formulation and compared against a control with no flavonoid. Maillard-derived reaction products were measured using colorimetry, fluorescence spectroscopy, chromatography, and other product quality attributes were assessed using a texture profile analyzer. The results revealed that luteolin treated cookies reduced fluorescence units by 44% against the control while the other flavonoids exhibited lower values (4% for eriodictyol to 21% for catechin), likely suggesting a higher degree of inhibition of Maillard reaction intermediates (MRI) and melanoidins in cookies. Furthermore, catechin apparent recovery in cookies was considerably lower (47%) vs the other flavonoids (64 – 70%), which was likely due to a greater participation of catechin and its thermal isomerization/degradation products in the reactions that inhibit MRP formation. Although further research is needed to determine the mechanistic details, the higher inhibitory effect of luteolin might be attributed to the C2 = C3 double bond conjugated with the C4 carbonyl in the flavone C-ring, whereas the distinctive hydroxyl group at C-3 on the C-ring of catechin may result in catechol oxidation, electrophilic carbonyl trapping, A-ring C6/C8 reactivity, degradation/epimerization, and polymerization. Overall, the results suggest that structural differences among the tested flavonoids played a key role in inhibiting the formation of Maillard reaction products, indicating the potential to manipulate ingredients and process adjustments for better understanding of the structural effects of flavonoids on Maillard reaction. Graphical Abstract Created in BioRender. Teferra [1] https://BioRender.com/p1fdfye