Effects of Gingerbread Cookie Enrichment with Native and Supercritical CO₂-Defatted Burdock Seeds

Burdock (Arctium lappa L., Asteraceae) seeds, a rich source of dietary fibre, proteins, essential and fatty acids, also contain high levels of polyphenols and lignans, especially arctigenin and arctiin. This study investigated the incorporation of native and supercritical CO₂-defatted burdock seed flour into gingerbread cookies formulated with sweetener xylitol compared to burdock seeds' free sugar-based and xylitol-based cookies as a control. Arctiin was the dominant lignan in both native and defatted seed flours (68.30 and 75.16 mg/g, respectively), while isochlorogenic acid was the most abundant phenolic acid (7.01 and 7.86 mg/g, respectively). Among enriched formulations, xylitol cookies with defatted burdock seed flour exhibited the highest soluble dietary fibre content (0.29 g/100 g) and reduced hardness, comparable to the xylitol control. All samples achieved "good" sensory quality (18.33-19.65 points), with no significant differences among formulations (p > 0.05). Storage studies (60 days) under varying temperature and light conditions revealed a significant decline in sensory quality only for sucrose-based control cookies stored at 40 °C. The concentrations of major phenolic compounds remained stable under all storage conditions. These results demonstrate the technological and nutritional potential of defatted burdock seed flour as a functional ingredient in bakery products.