Optimization of process parameters for the development of finger millet based multigrain extruded snack food fortified with banana powder using RSM.

Extrusion cooking is a high temperature short time process where food materials are cooked in a barrel with a combination of pressure, moisture and temperature. In this study a finger millet based snack product fortified with banana powder is extruded with a combination of rice flour, corn flour and cheese and its properties are studied. In addition to that the parameter for extrusion cooking of the snack product is also optimized. Response surface methodology was used to optimize the process parameters like barrel temperature (118-122 °C), extruder rpm (345-355) and banana powder concentration (1-4 g) on physical and functional properties of extruded snack food based on finger millet. Central composite design with three levels, three factors is used for optimization. Analysis of variance was used to study the effects of process parameters. Regression analysis is also done for variability and it is fitted to a second order quadratic model with coded value for each response. Based on Analysis of Variance model confirmed the fitness for dependent variables.