A method of making granular extrudate by extruding a starch-containing admixture from an extruder into an extrudate discharge chamber in gas flow communication with a discharge conduit that transports the granular extrudate away therefrom in gas turbulently flowing therethrough. During transport of the granular extrudate from the discharge chamber and through the conduit in the flowing gas, the gas quenches the granular extrudate cooling and drying the granular extrudate without heating it. Quenching reduces the granular extrudate temperature by at least 15° Celsius and moisture content to no greater than 13%. Quenching prevents shrinkage and densification of the extrudate including when cut into pellets. Quenching also prevents retrogradation, crystallization/recrystallization and solubilization of cold-water soluble binder formed in each pellet during extrusion. This produces extruded sorbent pellets which are water and oil sorbent, which clump when wetted, and which are well suited for use as cat or animal litter.