Functional cake production from red rosehip (Rosa canina L.) and black rosehip (Rosa spinosissima L.) fruits supplied from Bayburt province

Aim: The aim of this study was to evaluate powdered red rosehip (*Rosa canina* L.) and black rosehip (*Rosa spinosissima* L.) fruits collected from Bayburt province as functional ingredients in cakes, to determine their quality characteristics, and to assess their consumer acceptability. Material and Method: Seven different cake formulations, including a control group, were produced by replacing wheat flour with RC (*Rosa canina* L.) and RS (*Rosa spinosissima* L.) powders at levels of 5%, 10%, and 15%. The physicochemical, rheological, and organoleptic properties of the functional cakes were comprehensively evaluated. Results: RS powder exhibited higher pH, moisture, Fe, K, Mn, total phenolic content, total flavonoid content, and antioxidant activity than RC powder. Evaluation of the colour parameters (L*, a*, and b*) showed that RC had lighter, redder, and more yellowish colour tones than RS. The addition of RC and RS powders caused a significant decrease in the pH values of both the dough and the cakes. Compared with the control group, the highest ash content was observed in the RC15 and RS15 groups (1.22±0.03%), while the highest moisture content was found in the RS15 group (23.39±0.47%). The specific volume of all cake treatments decreased compared with the control group. The incorporation of RC and RS powders increased total phenolic content, total flavonoid content, and antioxidant activities (DPPH and FRAP), with the greatest increases observed in cakes containing RS powder. The crumb colour of cakes containing RC powder was darker, redder, and more yellowish than that of the control group, whereas cakes containing RS powder were darker and redder but less yellowish. Sensory analysis revealed statistically significant differences among the groups in crust colour, crumb colour, taste, aroma, and overall acceptability, with the highest scores obtained for the RS15 cakes. Considering all evaluated parameters, the RS15 group was identified as the best-performing formulation. Conclusion: RC and RS powders improved the physicochemical and organoleptic properties of the final product and demonstrated high functional and nutraceutical potential as food ingredients. In particular, the RS15 cake formulation emerged as the most suitable and innovative approach for the development of functional cakes compared with the other formulations.