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The inclusion of dietary fibers into food matrix has been widely reported due to its potential health benefits. Extrusion processing continually increasing attention as it has huge potential to deliver fiber enriched products such as breakfast cereals and expanded snacks. Previous researches were mainly focused on the optimization of the extrusion conditions and formulation to improve product texture and overall acceptability, whereas the relationship between the molecular structure and extrudate characteristics has yet been established. Blends of insoluble (Cellulose and lignin), soluble (Pectin) and natural fiber sources (Tomato pomace and sugar beet pulp) were prepared with replacement of corn flour and evaluated for physicochemical, dynamic rheological, pasting (RVA) and thermal properties (PTA). Pectin and sugar beet pulp showed highest water holding capacity of 6.37 g/g and 6.53 g/g respectively. Highest hydration capacity was observed with sugar beet (0.022 ml/g), lowest with corn flour. Highest oil holding was observed for cellulose (2.22 g/g) whereas lowest for pectin (0.84 g/g). From RVA, highest peak viscosity, breakdown and setback values of 5160, 747 and 7973.5 cP respectively were observed for 1 % cellulose whereas lowest values of 2150, 121 and 3770.5 cP were observed with 2 % pectin. Amplitude dependent behavior of pectin and amplitude-independent nature of insoluble fibers and control was revealed. <i>G’ </i>was found decreased with fiber addition. Higher <i>Tf</i> values were observed for all fibers as compared to control corn flour (147.7 °C) at 14 % moisture conditions whereas no clear trend observed at higher moisture conditions. Soluble dietary fiber will be of better choice for snacks due to lower oil holding capacity, peak viscosity, breakdown, final viscosity and amplitude dependence nature of elastic modulus (<i>G’</i>) which will result in better expansion.