Nutritional and technological characterization of rosehip seed flours as a functional ingredient in common wheat bread

This paper investigated the effects of adding 3% and 5% seed flours of three rose species cultivated in Sicily (Rosa canina L., Rosa micrantha Borrer ex Sm and Rosa rugosa Thunb.) to wheat flour and bread. Rosehip seed flours were rich in macro-elements, especially Ca and K. R. rugosa seed flour had a protein content higher than the others (13.0 g/100 g d.m.). A very high crude fiber content was observed in rosehip seed flour (between 43.74 and 52.16%), but also in the blends it was high (1.56–2.82%) compared to the control. Compared to wheat flour, gluten index and amylase activity were lower in the blends. Technologically, all the blends showed a longer mixing time than the control wheat flour, probably due to the higher amount of fiber competing with protein for water absorption, thus delaying dough formation. The addition of rosehip seeds flour had a positive effect on the leavening process (leavening rate + 1.7 times higher in R. rugosa 3%), while it did not alter the water and oil binding capacity. The bread obtained showed a reduction in volume (540.00 cm3), while the texture profile analysis revealed a greater hardness (7.49 N in R. rugosa 5%) and a decrease in springiness, gumminess and chewiness. These data suggest less elastic and chewy bread. The addition of rosehip seed flours to wheat flour affected the color of the breads, giving reddish tones, especially with the addition of R. rugosa 5%, with an increase in the red index values in both the flour (0.04) and the bread (4.73). The addition of R. rugosa and R. micrantha seed flour to wheat flour gave promising technological results, with R. micrantha increasing amylase activity. This suggests their potential use as baking improvers.