Dried Sourdough as a Functional Tool for Enhancing Carob-Enriched Wheat Bread

Functional bread development with clean-label ingredients remains a technological challenge due to the negative effects of certain functional additives on dough rheology and bread quality. The aim of this study was to evaluate the effectiveness of dried sourdough as a natural improver in carob-enriched bread. Dough formulations included 10–20% carob flour as a partial replacement of wheat flour, with dried sourdough added as a dough improver at 5–10%. The results demonstrated that the addition of 10% dried sourdough increased maximum creep compliance of dough with 10% and 15% carob flour by 26% and 56%, respectively. The addition of 5% and 10% dried sourdough to dough with 10% carob flour decreased its Newtonian viscosity by 24% and 36%, resulting in improved dough handling. Crumb pore structure was enhanced by the addition of 5% dried sourdough, with average pore surface area increasing around 2.5 times in breads with 15% and 20% carob flour. Incorporation of dried sourdough reduced bread hardness and chewiness by up to 40% in samples with 15% carob flour and by 20–30% in samples with 20% carob flour. Sensory properties of crumb structure (crumb development, pore fineness, elasticity and crumbliness), which were adversely affected by carob flour addition, showed varying levels of improvement by the addition of dried sourdough. These results demonstrate the feasibility of using dried sourdough as a natural improver in functional bakery formulations, supporting the development of clean-label products without synthetic additives.