Effects of hydrocolloids (arabic gum, guar gum, and xanthan gum) on the physicochemical and rheological properties of whole-barley fortified cracker flour were determined using solvent retention capacity, alveograph, and Mixolab profiles. Results showed that the water absorption of whole-barley fortified cracker flour was reduced by the additional arabic gum. Besides, arabic gum was more effective in reducing the resistance to inflation and improving the extensibility of whole-barley fortified dough. Mixolab parameters indicated that the weakening of gluten proteins and the rate of starch retrogradation in whole-barley fortified cracker dough were reduced by the presence of arabic gum. Guar gum and xanthan gum promoted the rate of protein breakdown, but slowed down the starch gelatinization and retrogradation rate during the Mixolab heating-cooling cycle. In conclusion, involved arabic gum rather than guar gum or xanthan gum is benefit to improve the baking quality of wholebarley fortified saltine crackers.
Authors:M.A. Elfattah, R.M. Elsanhoty, M.F. Ramadan, and M.O. Osman
The main objective of this work was to evaluate the composition, nutritional, physical and rheological properties of wheat flour and dough from genetically modified wheat (Triticum aestivum L.) Hi-Line 111 (GMW) compared to conventional wheat (non-GMW). Analyses were conducted to measure the proximate chemical composition with references to 18 components including total solid, protein, lipids, crude fiber, ash, carbohydrate, minerals, amino acids, and fatty acids. In addition, physical and rheological properties such as water absorption, arrival time, dough development time, stability value, dough weakening value, extensibility of dough, resistance to extension, and ratio of resistance/extensibility were evaluated. The results showed that there were no significant differences between GMW and non-GMW in terms of chemical composition. Results revealed the presence of saturated and unsaturated fatty acids wherein there were no significant differences between GMW and its counterpart in the levels of fatty acids. In addition, there were no significant differences on the levels of amino acids. In addition, there were no significant differences between the GMW and non-GMW in the physical and rheological properties. From these results, it can be concluded that GMW Hi-Line 111 is confirmed to have nearly the composition and rheological properties as non-GMW.
Authors:S. Osipova, A. Permyakov, T. Mitrofanova, V. Trufanov, M. Ermakova, A. Chistyakova, and T. Pshenichnikova
For six wheat varieties with different quality it was shown that GSH-dependent protein-disulphide oxidoreductase (TPDO) increases the activity to the third week after anthesis, a period of maximum synthesis of storage proteins in wheat kernels. The study revealed a correlation between TPDO activity in maturing kernels and dough stiffness. The addition of exogenous TPDO to flour significantly increased dough extensibility (from 17 to 49% for cultivars with different quality), which implies the ability of the enzyme to disrupt SS bonds in high-molecular weight gluten polymers.
Authors:S. Peighambardoust, M. Ghamari, and S. Naghavi
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, P.J. , Monaghan , J.M. , Evans , E.J. , Shewry , P.R. , McGrath , S.P. 1999 b. Variation in the breadmaking quality and rheologicalproperties of wheat in relation to sulphur nutrition under field conditions . J. Cereal Sci . 30 : 19 – 31