Rheological properties and baking quality of commercial durum wheat meals used to make flat crispy bread

Four commercial semolinas and four low-grade semolinas (LGS) samples were used in this study to make flat crispy bread (Carasau). The meals, doughs, and bread were compared with respect to a set of physical, chemical, and textural characteristics, and the bread evaluated by a trained sensory panel. LGSs had a higher extraction rate (higher ash content), finer granularity, and a higher damaged starch content than semolinas. The study revealed the key role of dry gluten content in determining hydration capacity of the dough, whereas damaged starch affected water absorption only in semolina samples. Gluten index and the ratio of gluten tenacity to extensibility (alveograph P/L ) were significantly correlated with the weight of the dough discs following sheeting and molding. The panelists gave the highest quality score to the bread with the highest values of crackling and hardness. Textural and sensory attributes were both correlated with one another, and with gluten strength and tenacity, but not with the gluten content of the meal, which only affected final moisture content of the bread. Meal samples with a more tenacious and elastic gluten were more suited to produce flat crispy breads. The yellowness of durum wheat bread could not be predicted by measuring the color of the meal with a reflectance method.