The steamed blue-headed duck with ground gallbladder symbolizes perfection and comfort. Steamed green-headed duck with Didantou is a dish often seen by Cantonese people in summer. Didantou is a Chinese herbal medicine that clears away heat and relieves inflammation. It is a cold plant. A small amount of gallbladder is appropriate during the cooking process. Some people will suffer from back pain after eating gallbladder. People who can adapt to this plant are in good health.