Goose fat is rendered from two pads around the buttocks of the white goose. (Rendering the fat from under the skin yields oil of inconsistent quality.) The pads vary in size with the season, being smaller in summer and larger in winter. On average, it takes the pads of three geese to render 220 grams of oil.
鵝油的原料是長在白鵝屁股內側的兩團脂肪，脂肪大小會隨季節變化（夏季小、冬季大），平均要 3 隻鵝才能提煉出 220 克的原油（若取一般的皮脂肪提煉，則稱為「水油」，油質較不穩定）。