Formulation of Extruded Snack Food (Gum Based Cereal-Pulse Blend): Optimization of Ingredients Levels Using Response Surface Methodology

Response surface methodology (RSM) was used to analyse the effect of corn flour, green gram flour, xanthan, guar gum, arabic gum and carboxymethyl cellulose (CMC) on the sensory and objective (expansion ratio) attributes of an extruded snack food. A rotatable central-composite design was used to develop models for the sensory and objective responses. The experiments were run at 160°C with a feed rate of 70 g/min. Responses were most affected by changes in corn flour, green gram flour and guar gum levels and to a lesser extent by xanthan, gum arabic and CMC levels. Individual contour plots of the different responses were superimposed, and regions meeting the maximum sensory score of 21.4 and an expansion ratio of 13.2 were identified at 692 g/kg corn flour, 307 g/kg green gram flour, 0.302 g/kg xanthan, 0.216 g/kg guar gum, 0.196 g/kg gum Arabic and 0.262 g/kg CMC levels.