Enhancing the Nutritional and Sensory Quality of Tartary Buckwheat Cookies Through Solid-State Fermentation with Eurotium cristatum and Baking

Tartary buckwheat (Fagopyrum tataricum), a medicinal and edible crop, is valued for its richness in flavonoids and polyphenols, which confer antioxidant and hypoglycemic activities. Eurotium cristatum, a dominant fungus crucial for the quality of Fuzhuan tea, produces unique aromas and metabolites. This study developed cookies by replacing 20% of low-gluten flour with Tartary buckwheat flour that had undergone solid-state fermentation with E. cristatum followed by baking. Compared to cookies containing non-inoculated buckwheat flour, the fermented cookies contained significantly higher levels of total flavonoids (4.97 mg/g) and polyphenols (2.31 mg/g), and exhibited markedly enhanced antioxidant activity, as evidenced by a 16.4% higher ABTS radical scavenging rate and a 42.5% greater ferric reducing power. The fermented cookies also exhibited improved textural and sensory properties, a unique aroma profile characterized by pleasant floral notes, and a more homogeneous microstructure. HS-SPME-GC-MS analysis indicated that the optimized flavor resulted from the upregulation of key pleasant aroma compounds (e.g., (E)-2-nonenal, anethole) and the suppression of specific off-odor compounds (e.g., 2-ethyl-3,5-dimethylpyrazine, p-cresol). In conclusion, solid-state fermentation with E. cristatum followed by baking, effectively improves both the nutritional and sensory characteristics of Tartary buckwheat cookies, providing a viable strategy for developing novel, health-promoting bakery products with an appealing compelling flavor profile.