INFLUENCE OF THE STARCH GRANULE SURFACE ON THE RHEOLOGICAL BEHAVIOUR OF WHEAT FLOUR DOUGH (original) (raw)

Rheological Properties of the Wheat Flour Supplemented with Different Additives

Evaluation

One characteristic of the Romanian wheat flour in the recent years consists of high values of the falling number. The aim of the present study was to explore the Mixolab device to characterize the thermo-mechanical behaviour of flour supplemented with different additives that contain α-amylase. Mixolab parameters C4 and C5 were found to be lower in samples with high doses of additives containing α-amylases. The increase of the α-amylase dose reduces the dough stability. The samples that contain higher doses of additives presented low values of the β slope, which gives indications about starch gelatinization. The samples with reduced α-amylases activity showed high values of the γ slope.

Wheat flour non-starch polysaccharides and their effect on dough rheological properties

Industrial Crops and Products, 2011

Wheat (Triticum aestivum L.) flour is able to form dough with unique rheological properties that allow bread making. It is well known that wheat protein content affects dough rheological properties, but there is not enough evidence about the role of other minor flour constituents. One such minor constituent is non-starch flour polysaccharides, which are mainly pentosans formed by a xylopyranosyl linear chain branched with arabinofuranosyl residues. Their spatial distribution and branching pattern can affect their relationship with gluten forming proteins and thus influence their functional properties, the dough rheological properties, and thereby the flour baking quality. In this study the content and structural characteristics of non-starch polysaccharides were investigated, as well as their influence on some dough physicochemical parameters. Five different wheat flours samples milled from Uruguayan wheat varieties with diverse rheological and breadmaking properties were used in this study. Water soluble flour polysaccharides were extracted and the amount of pentosans was determined by the orcinol-HCl method. The pentoses composition was determined before and after acidic hydrolysis of the water soluble polysaccharide fractions by GC. No free pentoses were detected in any of the assayed flour samples, so the pentoses composition found in the hydrolyzed samples was attributed to the non-starch water soluble polysaccharides. Water unextractable non-starch polysaccharides were determined by difference between the total and the soluble non-starch polysaccharides flour content.

Original article Relationship between physicochemical and rheological properties of starches from Indian wheat lines

Starches from nine Indian wheat lines were evaluated to study the relationships between physicochemical and rheological properties. Large granules (>15 lm) were present in the highest proportion followed by medium (5-15 lm) and small granules (<5 lm). Amylose content ranged between 27.4 and 37.2%. Starch with the highest proportion of large granules (68.9%) showed higher values of G¢ peak (576 Pa) and G¢ final (432 Pa). Amylose content showed positive relationships with retrogradation, gel firmness, gumminess and adhesiveness while negative with springiness. Cooked starch pastes with the highest amylose content (37.2%) had higher DH ret (0.88 J g )1 ), G¢ ret (361 Pa), adhesiveness (1.48 Ns), firmness (0.45 N) gumminess (0.22 N) and the lowest springiness (0.88). Amylose-lipid complex (AML) dissociation showed negative relations with swelling power, G¢ peak , G¢ breakdown and breakdown viscosity (r = )0.779, )0.66, )0.771 & )0.775, respectively, P < 0.05) while positive relationship with pasting temperature (r = 0.775, P < 0.05).

Dynamic rheological properties of wheat flour dough and proteins

Trends in Food Science & Technology, 2007

Dynamic rheological testing has become a powerful and preferred approach for examining the structure and the fundamental properties of wheat flour doughs and proteins because of its characteristic and sensitive response to the structure variation of wheat flour doughs and proteins. In the present article, the dynamic rheological properties of wheat proteins and flour doughs were reviewed. Influences of various additives on the rheological properties of gluten proteins and flour doughs are illustrated and the component interactions are emphasized. Moreover, theoretical analyses concerning the relationship between rheological behavior and structure are summarized.

Rheological behaviors of doughs reconstituted from wheat gluten and starch

Journal of Food Science and Technology, 2011

Hydrated starch-gluten reconstituted doughs were prepared and dynamic rheological tests of the reconstituted doughs were performed using dynamic strain and dynamic frequency sweep modes. Influence of starch/gluten ratio on rheological behaviors of the reconstituted doughs was investigated. The results showed that the reconstituted doughs exhibited nonlinear rheological behavior with increasing strain. The mechanical spectra revealed predominantly elastic characteristics in frequency range from 10 −1 rad s −1 to 10 2 rad s −1. Cole-Cole functions were applied to fit the mechanical spectra to reveal the influence of starch/gluten ratio on Plateau modulus and longest relaxation time of the dough network. The time-temperature superposition principle was applicable to a narrow temperature range of 25°C~40°C while it failed at 50°C due to swelling and gelatinization of the starch.

Rheological properties of wheat flour dough and gluten. Effect of water content and native lipids

2003

Dough is the intermediate product in the transformation of fluurs to bread or to other baked products. Rheological properties of dough and gluten are important since they affect the quality of the baked product. They are also important because the provide information on dough structure. As with any other material, the rheological properties of dough are determined by its composition (protein, starch, lipid and water content) and structure

Starch gelatinization as measured by rheological properties of the dough

Journal of Food Engineering, 2010

Rheological properties of gluten-free dough (GFD) as well as conventional gluten containing dough (CGD) during processing were measured. Both CGD and GFD were examined in terms of mechanical spectrum, in the frequency range 0.1-10 Hz, at constant deformation c = 0.01, at different temperatures. As a result changes in viscoelasticity of dough during selected stages of bread production (mixing-proofing-baking) were obtained. Changes in complex moduli of GFD and CGD, at a frequency of 1 Hz were measured. Curves obtained showed the changes in tan(delta) (phase shift) with time and allowed calculations of first derivatives which indicated the temperatures of gelatinization of the starches present in the studied systems (wheat, corn and potato). The results of rheological measurements were compared to DSC results of appropriate dough samples. It was concluded that rheological measurements followed by derivative calculations are useful for determining the gelatinization temperature of starches included in the dough.

Dynamic rheological characteristics of wheat flour–water doughs. Effect of adding NaCl, sucrose and yeast

Food Hydrocolloids, 2006

Dynamic oscillatory rheology of a basic dough containing only wheat flour and water (control sample) were studied. Individual effects of adding sucrose (10 and 20%), NaCl (1.2 and 2.4%) or yeast (2, 4 and 8%) to the control sample were studied. Mechanical spectra at 25 8C and at 80 8C were obtained and dough behaviour during heating to 80 8C was studied. Each of the three ingredients affected the rheological behaviour at 25 8C, causing a lowering of dough consistency as can be observed through the drop in the G 0 and G 00 values and an increase in the starch gelatinisation temperature. At 80 8C the behaviour of the doughs prepared with sucrose or with NaCl did not differ from that of the control but the fermented doughs still presented lower viscoelastic moduli values than the control.