Response surface methodology was used to determine the optimum processing conditions that yield maximum apparent viscosity and extraction yield and consistency coefficient with minimum protein content and flow behavior index during extraction of Qodume shirazi seed gum. Extraction temperature (25–85C), pH (4–10) and water : seed (20:1–60:1) were the factors investigated. Experiments were designed according to Central Composite Face Center Design with these three factors, including central and axial points. The response surfaces showing the interaction of process variables were constructed. Solution with 3% concentration of each gum with different extraction methods were made to evaluate the flow properties of gum extracted from Qodume seeds. The Power-law model was successfully applied to fit the shear stress versus shear rate data of gum solution. The flow behavior indices, n, varied in the range of 0.25–0.41. The consistency coefficients, k, were in the range of 5.5–8.62 Pa•sn. Applying desirability function method, optimum operating conditions were found to be extraction temperature of 36.3C, pH of 4 and water : seed of 40:1. At this optimum point, apparent viscosity, extraction yield and protein content, consistency coefficient, flow behavior index were found to be 855.9 (mPa•s), 287.3 (g/kg), 1.27 (%), 8.27 (Pa•sn) and 0.29, respectively.

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