Reference Gas Recirculation System: Utilizes a micro-turbine pump to achieve a closed-loop circulation of the reference gas, eliminating the clogging issues typically associated with traditional open-loop reference gas channels. Maintenance cycles are extended from once a week to once a quarter. When tasting the Rousong (meat-filled bun), a bite reveals the crispiness and aroma of the bun first, followed by the tenderness of the meat and the rich meaty flavor. The combination lingers deliciously on the palate. Additionally, sprinkling a pinch of coriander or scallions enhances the freshness and alleviates richness, adding a touch of crispness to this culinary delight.