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System variables such as specific mechanical energy (SME), pressure before the die (P) and net torque (T) are important system variables in extrusion cooking. These parameters reflect the combined effect of machine parameters (screw speed, L/D ratio, compression ratio, screw configuration, temperature profile along the length of the barrel section and feed rate) and feed properties (;food micronutrients; particle size and moisture content of the feed) on system performance which are often used as parameters for scale-up operations to large capacity commercial applications. Our laboratory scale extrusion experiments with chickpea flour showed that the system variables, specific mechanical energy (SME), pressure (P) and net torque, were highly correlated with the process variables die temperature and moisture content of the feed. System variables were further correlated with extrudate characteristics such as expansion ratio, in vitro protein digestibility, water activity, moisture content of extrudate and color. The result indicated that expansion ratio, IVPD and moisture content were highly correlated with SME and P with coefficient of correlation above 0.85. Water activity and color were also correlated with system variables with coefficients of 0.75 and 0.65, respectively. The results show promise for using system variables for effective control and scale up of large capacity commercial extruders to replicate production of newer products developed in laboratory.