Process Optimization of Sorghum Based Extruded Snack Incorporated with Tilapia (Oreochromis niloticus) Mince using RSM

Abstract

A study was carried out to optimize processing condition for developing an acceptable ready to eat extruded snack using Response Surface Methodology. Tilapia mince was incorporated with a composite blend of sorghum grits and corn flour, which was used as base material for this study. The snack was prepared with composite flour mixture of Sorghum (40-70%) and corn (20-40%) with tilapia fish mince (10-20%) using twin screw extruder. The effect of independent variables such as temperature (120- 130oC) any screw speed (300-400 rpm) on dependent variables such as bulk density, expansion ratio, hardness, specific mechanical energy was analysed. Mixture response design with 27 trials were carried out to study optimisation of physical parameters and found that sorghum 44.87%, corn 40%, tilapia mince 15.13%, at 130oC and 343 rpm screw speed was found to be ideal for the expanded extruded snack The physical properties of the product were statistically significant with R2 value >0.85, for all models. The study explores the possibility of utilization of low-cost underutilised sorghum and freshwater fish tilapia in product development with improved nutritional quality.