Effect of Different Types of Sourdough on Wheat Dough Rheology and Bread Quality

Inactive sourdough contains fermentation-derived compounds that may influence dough properties and bread quality. This study investigated four commercial inactive sourdoughs—wheat-based Sapore Rigoletto (SR) and Medea (SM), and rye-based Sapore Othello (SO) and Traviata (ST)—added at 1–4% to wheat bread without added salt, compared with a 0% control sample (CS). Dough rheology, fermentation, bread physical properties, texture, CIELab color, sodium content, and sensory acceptability were evaluated. Increasing sourdough concentration intensified acidification, with 4% SO yielding the lowest pH (4.18 versus 5.44 for the CS). Sourdough addition modified tenacity and generally reduced extensibility and baking strength. Low incorporation levels (1–2%) improved gas production and, in selected formulations, loaf volume and crumb softness. At 1% SO, specific loaf volume increased from 3.40 to 3.75 cm3/g and hardness decreased from 16.60 to 8.24 N. Higher levels (3–4%) generally increased firmness and reduced elasticity. CIELab coordinates, browning index, and whiteness index indicated increased crust browning and reduced crumb whiteness. Sodium decreased with SR and SM but increased with SO and ST, reaching 22.20 mg/100 g at 4% ST versus 7.27 mg/100 g for the CS. Overall, selected 1–2% additions improved technological properties of wheat bread without added salt.