The absence of gluten protein makes the rice flour doughs difficult to handle when flattened/sheeted products are to be prepared. The rheological, sensory and microstructural changes in rice flour doughs having gum Arabic (0% to 5%, w/w) and moisture contents (44% to 50%) were studied for improving the dough handling characteristics. Rheological parameters like storage modulus (G') and complex viscosity (η*) decreased with an increase in moisture content while loss angle (δ) increased. A power-law type equation was suitable to relate angular frequency (ω) with G', G", and η* (0.814 ≤ r ≤ 0.999, P ≤ 0.01). An increase in gum and moisture contents increased δ from 6.9° to 15.5° but decreased the energy required for compression/flattening. The 6-element spring-dashpot model was suitable (r ≥ 0.991, P ≤ 0.01) for creep curves. The sensory panel had the opinion that dough with a low to moderate hardness between 3 and 4, and stickiness of ≤ 3.5 was suitable for the purpose of flattening in relation to the preparation of sheeted/flattened products; the appropriate condition for dough formulation was with the moisture and gum contents of 47.0% to 47.9% and 1.55% to 2.25%, respectively to offer the desirability index between 0.50 and 0.52. The microstructure of the rice flour dough in the absence of gum Arabic appeared to possess loosely bound flour particles. The presence of gum provided a coating on flour particles to yield dough having good cohesive microstructure.

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The effects of rice flour (50-56%, w/w) and gum Arabic (0-5%, w/w) on the physical, sensory and structural features of the fried dough strands were investigated. Up to 25.8% reduction in oil was possible by the incorporation of gum Arabic. The wide variations in failure force (13.8-25.3 N) and failure strain (11.0-28.6%) indicated the formation of snacks varying in texture from a soft-to-bite brittle product to a hard-to-eat less brittle sample. The snacks possessed a porous microstructure with air cells, pores and vacuoles; the cell walls were more than 100 μm in thickness. The textural parameters like failure force, failure energy and failure stress behaved in a similar manner in the principal component analysis biplot. High moisture content in the dough decreased the sensory acceptance of the fried snacks. The high desirability index of 0.9 could be achieved with a high level of rice flour (56%, w/w) while gum Arabic content was between 3.50 and 3.75% (w/w).

Flowable food materials express complex flow behaviour and are conventionally subjected to individual time-independent and time-dependent experiments. The present study proposes a single experiment to determine both these characteristics simultaneously in addition to determining the 'isoviscosity' to quantify and compare these properties by using a model food system like chickpea flour dispersion. The method employed here consists of the generation of five loops having increasing and decreasing shear-rates along with yield stress measurement in between them. The conventional rheological model like Herschel-Bulkley equation has been employed to determine the rheological properties that are affected as the number of loop increases. Though used in a model food system, the method is also expected to find applications in non-food non-Newtonian liquid systems for convenience.