Mutton fat is rendered using dry rendering (heating without water) or wet rendering (using steam or water), typically at 100–120°C. The liquid fat is then filtered to remove solids and dried to eliminate moisture, which can interfere with the transesterification process. If free fatty acid (FFA) levels are high, a pre-treatment step (acid esterification) may be needed. The GlobeCore USB biodiesel plant can process mutton fat directly after rendering, with integrated systems for heating, mixing, and separating glycerin, making it efficient for on-site or scaled-up production.