Impact of Sourdoughs, Enzymes, and Their Combinations on Gluten-Based Bread Quality

The study investigates the impact of sourdoughs made with different flours (white wheat, wholemeal wheat, and barley) and specific enzymes (laccase, lipase, and hemicellulase) on the technological properties of gluten-based wheat breads, thereby exploring the combined role of sourdough and enzymes. Three levels of each sourdough (20, 30, and 40%) were tested, and the optimal level was then used to evaluate the impact of individual and combined enzyme treatment. Pasting properties and FT-IR analyses of the flours were evaluated. White wheat flour displayed the highest peak viscosity (353.50 mPas) and final viscosity (526.50 mPas). β-sheet structures predominated in all samples, although they were most prevalent in wholemeal wheat flour (51%) as opposed to white wheat flour (47%) and barley (47%). Sourdough breads exhibited better texture and moisture retention at 40% inclusion than at other levels. After 72 h, white wheat sourdough maintained the highest specific volume (3.71 cm3/g), while barley sourdough retained the most moisture (38.83%) and the lowest chewiness and hardness results, suggesting better softness and crumb retention. Whereas for enzyme treatment, they had different effects. White wheat and wholemeal wheat sourdough breads treated with enzymes had decreased hardness, chewiness, and gumminess; barley sourdough breads with enzymes were negatively affected by the texture. Correlations and multivariate analysis reveal that bread texture is strongly influenced by the type of sourdough and enzymatic treatment. Higher doses of laccase or hemicellulase improve softness in wholemeal-based sourdough bread, while excessive lipase leads to a firmer and less pleasant crumb.