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The study aims to compare three methods used for the evaluation of water absorption of wheat flour: a) a direct method consisting of a standard procedure on a Farinograph-E device and b) two indirect methods, namely NIR spectroscopy and centrifugation. Forty-four samples of Czech food wheat were collected from the harvest year 2021. Namely, 23 samples of food wheat from the standard maturity collection ‘SM2’ and 21 samples from the early maturity collection ‘EM2’. All wheat samples were ground to obtain wheat flour of fine granulation. The flour samples were characterised by protein and ash content of 10.55-14.75% and of 0,59-0.63%, respectively. The water absorption ranged from 55.7% to 63.2% flour weight (Farinograph standard procedure), 60.1-67.1% flour weight (NIR spectroscopy), and 67.6-77.2% flour weight (centrifugation). Based on the results obtained by ANOVA statistical analysis, no significant difference was found for all qualitative parameters of SM2 and EM2 (p = 95%). According to the mentioned methods for both indirect determinations of water absorption in the sets SM2 and EM2, the prediction of the standard farinograph water absorption was more accurate using the NIR technique (minimal and maximal pair differences of 1.01 and 6.86 percentage points, in contrast to 1.78 and 14.87 percentage points for the centrifugation method). Linear regression confirmed the primary importance of protein content for the water absorption values. Also, the ash content should be considered because it reflects the dietary fibre level, and the fibre influences the water absorption values as well.

To elevate dietary fibre content in wheat bread, additions of barley flour were tested (30%) alone, and in combination with 5% or 10% of chestnut and acorn flour. Acorn flour elevated dietary fibre content more effectively than the chestnut flour did (TDF up to 7.8%). Non-gluten nature of proteins in non-traditional raw materials also affected farinograph, extensograph and amylograph features, used for predicting bakery procedure. Technological parameters (Falling Number, Zeleny sedimentation value) decreased to nearly 30% compared to the wheat flour. Water absorption increased about 2% in total, especially owing to the chestnut presence in the composite flour. All three alternative crops slowed dough development, but the dough softening degree depended on their combination. Viscoelastic behaviour has worsened (mainly parameter extensograph energy), depending on the type and the addition of the non- traditional products in the tested mixtures. Changes of suspension structure were reflected in maximum viscosity, which became lower during the amylograph test. A significant worsening of the buns specific volume and vaulting reflected a partial dilution of the gluten network of the dough. The highest addition of the chestnut flour in the recipe caused a decrease to less than one half compared to the wheat product. By the principal component analysis, some rheological parameters, together with specific bread volume, were identified as principal for sample distinguishing. In terms of wheat flour and bread quality, barley flour addition in the mixtures had a prevailing effect on the tested tri-composites.