Effects of salep gum at concentrations of 0.5%, 1%, 3%, and 5% (w/w flour basis) and the Persian gum at concentrations of 0.5%, 1%, and 3% (w/w flour basis) and combination of the two gums at concentrations of 0.5% + 0.5%, 0.75% + 0.25%, and 0.25% + 0.75% on rheological properties of the wheat flour dough and quality of Taftoon bread were studied with regard to retardation of staling. Rheological (farinograph and extensograph) characteristics, staling, and organoleptic evaluations were performed on the dough and the resulting Taftoon bread. Statistical results showed that the salep gum at 5% and Persian gum at 3% (w/w flour basis) had a significant effect on the dough properties. Salep and Persian gums when each separately added increased and decreased dough water absorption, respectively. Both hydrocolloids increased the dough resistance to extension and decreased its extensibility. Persian gum shows dual nature in water absorption and some other baking properties. Textural studies revealed that addition of 5% salep gum (w/w flour basis) reduced the bread crumb firmness and delayed the staling process of the Taftoon bread. X-ray diffraction study also confirmed this result. 1. Introduction Bread, especially wheat bread, is widely consumed all over the world particularly in the developing countries and is an important source of protein and calories [1]. Bread is not spoiled by the microorganism or endogenous enzymes; however, its quality is lost by staling during storage [2]. Bread staling is a very complex process and many physicochemical changes occur that culminate in recrystallization of amylose and amylopectin [3]. There have been many approaches on how to retard the process, among which the most successful ones are the use of additives such as emulsifiers and enzymes [2]. There are several studies showing the potential use of hydrocolloids in baking industry as a way to retard staling [4–6]. Taftoon is one of the popular Iranian flat breads, produced from soft white wheat flours of higher extraction level. The bread has a round or oval shape, with the dimensions of 400–500？mm length, 400–500？mm width, and 2？mm thickness, with the average weight of 149-150？g. Ingredients of Taftoon bread are flour = 100？kg, water = 78–90？L, yeast = 450–650？g, and salt = 90–130？g. The chemical compositions of a loaf of Taftoon bread are crude protein = 10.47% dry mass, crude fat = 0.57% dries mass, crude fiber = 0.92% dry mass, ash = 2.53% crud mass, hydrocarbons = 85.5% dry mass, NaCl = 0.86% dry mass, and moisture = 26.87%, with the pH value of 7 and 389？kcal/100
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