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The technological quality of the protein fraction of wheat white flour (WW) was determined by the lactic acid Solvent Retention Capacity and by the Gluten Performance Index (LA-SRC and GPI; AACC method 56-11.01). Parallelly, Perten's standard Gluten Index test (GI; AACC method 38-12.02) was performed with that wheat control. Consequently, the same methods were applied to 9 bi-composite blends mixed at ratios of 90 : 10, 80 : 20, 70 : 30, 60 : 40, 50 : 50, ..., and 10 : 90 as WW replacement with one of the rye bread flours (RB), and the RB control itself. Unlike successful measurements in the case of the LA-SRC and GPI, washing gluten from the first 90 WW : 10 RB blend led to the clogging of the Glutomatic sieve, likely due to the interaction of wheat gluten with rye arabinoxylans. The discrepancy induced the development of a modification of the standard GI procedure; clogging was avoided by precipitating flour and centrifuging the swollen solid from suspension, similarly like in the SRC method. The settled residue transported to a standard sieve cassette was secondly centrifuged in the original apparatus Perten CF2015. The weighing of the over- flow and underflow of the sieve and the calculation of the results were performed according to the original GI method. For the WW control, the standard GI value was 90% and the modified Gluten Index value (GImodif) was 82%. As expected for WW-RB counterparts, the higher the portion of rye in the bi-composite blend, the lower the value of the GImodif. For the 50 WW : 50 RB blend and the RB itself, the GImodif values were 47% and 18% (the GPI values 0.66, 0.45, and 0.39, respectively). On the contrary, the LA-SRC demonstrated a convex course (118, 104, and 123%, respectively). In the plane of the principal components (PC), namely PC1 and PC2, the variables related to gluten quality formed 4 groups as a function of the stepwise change in the mixing ratio of WW and RB: i) flour protein content, GPI, and GImodif; ii) LA-SRC; iii) dietary fibre content and ash content; iv) water, sucrose, and sodium carbohydrate SRCs. However, the modified test procedure should be revised in wheat varieties characterised by a wider spectrum of protein quality, mixed with different types of rye flour (especially wholegrain one). [ABSTRACT FROM AUTHOR]

Additions of barley flour alone or with combination of chestnut and acorn flour (30%; 30+5%; 30+10%) were aimed at increasing the dietary fibre content in wheat bread. In this regard, enhance-ment by acorn flour elevated the dietary fibre by a greater extent (up to 7.80%) compared to barley or chestnut flours. Increasing the proportion of non-traditional raw materials also inuenced flour pasting properties during the amylograph test as well as the farinograph and extensigraph properties of non-fermented dough. In contrast to the wheat flour, analysis of Falling Number and Zeleny values showed a decrease in technological potential of flour composites of approximately 30%. Water absorption in-creased about 2 percentage points, mainly with enhancement by chestnut flour. All the non-traditional raw materials slowed dough development, whilst dough softening degree differed according to actual composition. Dough viscous and elastic properties worsened as shown by a decrease of in energy ab-sorbed, depending on the type and the addition of the non-traditional products. Changes in flour composition were reected in amylograph viscosity maximum, which became lower with increasing amounnts of chestnt and acorn flour. A significant worsening of the bread specific volume as well as of bread shape (vaulting) corresponded with a partial dilution of the gluten matrix. Compared to the wheat bread, 10% chestnut flour caused bread size to diminish to less than one half of the wheat loaf. Statistically, the principal features were water absorption, dough softening degree and extensigraph energy together with specific bread volume. In terms of wheat flour and bread quality, the inuence of barley flour overcame the effects of adding chestnut or acorn flours. [ABSTRACT FROM AUTHOR]

Wheat flour was fortified by 2.5, 5.0 or 10 wt. per cent of linseed fibre, gained from seeds of golden flax varieties Amon and Raciol and brown one Recital (granulation 500700 m), prepared from 2015 and 2016 harvests. Using analytical tests, namely sedimentation according to Zeleny and Falling Number, basic technological quality of flour composites was mostly independent on all three observed factors (harvest year, linseed variety and addition). Rheological tests included the farinograph, the extensigraph and the amylograph proofs. Enhancement by brown and yellow flax fibre significantly contributed to rise of farinograph water absorption and to dough stability shortening, directed mainly by addition level. Extensigraph curves course depended on dough resting time, higher differences between wheat control and flour composites were observed after 60 min dough resting. Linseed fibre weakened dough extensibility, and energy as area under curve also partially decreased about 3, 8 and 25% in average as portion of alternative materials in dough has risen. Compared to control, suspension viscosities of tested flour composite generally increased; the strongest effect was recorded for composite samples from harvest year 2016. During dough leavening, tested samples were differentiated according to maturograph dough resistance, and interaction of all three factors was identified. Regardless to variantion in dough machinability, specific volumes of composite bread samples were similar through whole sample setany unequivocal trend was found. Somewhat worse vaulting of bread was calculated for buns manufactured from raw materials of 2016 harvest. Reversely, linseed fibre produced in 2015 improved crumb softness, especially at 5% enhancement (about ca 50% in average). The lowest addition of linseed fibre resctricted biscuits spread during baking in the highest extent, but rising level of enhancement suppressed elevated dough elasticity. Both cereal products were considered as acceptable for common consumers. Multivariate PCA method verified changes mainly in protein visco-elastic properties, which were reflected in bread and biscuits quality in an opposite manner. Based on this statistics, quality of wheat controls was comparable in both harvest year if related to changes induced by linssed fibre. In opposite to this, technological and consumer’s parameters of flour composites and manufactured cereal products were statistically dependent of harvest year of linseed. As presumed, the lowest addition level brough the smallest changes; multiplied fortification caused gradual variation in results of all conducted proofs. Owing to high dietary fibre content in linseed fibre (over 50%), the medium dosage of the alternative material (i.e. 5% addition) could be recommended for praxis. [ABSTRACT FROM AUTHOR]

Wheat flour was fortified by 2.5 or 5.0 wt. per cent of linseed fibre, gained from seeds of golden flax varieties Amon and Raciol and brown one Recital (granulation 500 – 700 m), prepared from 2015 harvest. Technological quality of six flour composites was described analytically by Falling Number and Zeleny sedimentation test. Both screening methods shown a little impact on amylases activity and protein quality, respectively. Rheological tests included the farinograph, the extensigraph and the Rapid Visco Analyser (RVA) proofs. Additions of brown and yellow flax fibre significantly increased farinograph water absorption and shortened dough stability, somewhat stronger by addition of brown linseed fibre. Extensigraph curves course depended on dough resting time, higher differences between wheat control and flour composites were observed after 60 min dough resting. Linseed fibre supported dough extensibility, and energy as area under curve significantly decreased about 7 – 18%, mainly due to increasing alternative material portion in dough. In general, fibre is characterised as hydrophilic material, and pasting profiles of flour composites confirmed this experience. During dough leavening, tested samples were differentiated according to maturograph dough resistance; optimal leavening time of wheat-linseed fibre dough was shorter than control. Regardless described modifications in dough machinability, specific volumes of bread buns were similar though whole sample set. A weak worsening of buns vaulting reflected a partial dilution of dough gluten skeleton. Cut-off biscuits were characterised by gradually lowering spread ratio, correspondingly to elevated dough elasticity. Laboratory prepared elbow-pasta have the same cooking time as the control (8.0 min), and data variation could not be attributed to linseed fibre or addition level. All three cereal products were found to have acceptable sensory profiles. PCA method verified partial lowering of protein quality and pointed at tested sample differentiation according to linseed addition level. [ABSTRACT FROM AUTHOR]

Wheat flour substitution by barley one led to shortening of fermentation and leavening times (about 14-57% and 35-83%, respectively) as well as to lessening of dough volumes (about 25-75%), based on lowered protein quality (Zeleny value). Addition of barley flour affected specific bread volume; diminishing for wheat-barley blends 70:30 and 50:50 reached 30% and 43%, respectively. Volume of bread prepared from wheat-barley blend 70:30 enhanced by dehulled hemp wholemeal was the highest within the tested tri-composites set, achieving 130% of wheat-barley control; other hemp products caused the parameter decrease (from 8 to 33%). Within a group of bakery products containing 50% of barley fl our, hulled hemp wholemeal partially supressed negative effect of barley flour - specific bread volumes increased about ca 15%. Commercial fi ne hemp flour samples demonstrated a reversal influence - its addition resulted into lower buns size than wheat-barley control (about 3-34%). Between wheat flour and both groups of fl our tri-composites, PCA confirmed differences in dough and bread technological quality. Specific bread volume could be predicted according to maturograph dough elasticity, dough or bread OTG volumes. [ABSTRACT FROM AUTHOR]