Powder coatings have the great advantage to emit fewer volatile organic compounds (VOC) when compared to traditional solvent-based paints. To reinforce the ecological interest of this technology, recent research efforts have developed polyester resins from renewable resources. However, these novel bio-based resins tend to be more expensive than their petrochemical counterparts. So as to reduce the formulation cost, a lignocellulosic waste product was chosen to replace traditional mineral fillers in a polyester/hydroxyalkyl amide (HAA) bio-based formulation. For typical thermoset powder coatings, differential scanning calorimetry (DSC) is used for the characterization of cure. However, for polyester/HAA, detection of the enthalpy of reaction using DSC is difficult, therefore another technique is needed to determine the progress of reaction. The present work describes a method using torque rheology to follow the curing behaviour of powder coatings. The thermo-reactivity and the viscosity of the bio-based powder coatings containing renewable and low cost filler are discussed in relation to the quantity of filler in the formulations.