Rheological characteristics of wheat flour dough as influenced by ingredients of parotta

The effects of addition of salt (0.5%, 1.0% and 1.5%), sugar (0.5%, 1.0% and 1.5%), egg (2.5%, 5.0% and 7.5%) and refined groundnut oil (5.0%, 10.0%, 15.0% and 20.0%) on various rheological characteristics of dough, as measured by the farmograph, mixograph, extensograph and Instron universal testing machine, were studied. Addition of increasing amounts of salt, egg and oil increased farinograph stability from 3.5 min for the control sample to 9.5, 4.5 and 6.5 min, respectively and decreased to 3.0 min with sugar. The extensograph ratio figure, area increased with the addition of egg and decreased on addition of oil. The mixograph peak height increased when salt or egg was added, but decreased on addition of oil and addition of sugar produced no effect. Values of apparent biaxial extensional viscosity (ABEV), compressive stress, hardness and cohesiveness increased on addition of salt or egg, but they decreased on addition of sugar or oil. The force decay parameter value decreased with the addition of salt and egg, but increased when sugar or oil was added. The adhesiveness value decreased when salt or egg or oil was added, but increased with sugar; indicating thereby addition of salt or egg produces an increase in the strength and elasticity of the dough, on the other hand, addition of oil decreases the strength and viscosity of the dough. (c) 2006 Elsevier Ltd. All rights reserved.