There is a film on the surface of the freshly cooked red syrup.

It's a layer of grease. Red syrup is a kind of syrup made of extract, which is a red-brown viscous liquid with sweet and astringent taste. Mainly used for treating chronic tracheitis, with expectorant and antitussive effects. That film is the internal oil leakage, like the temperature of hot sugar water exceeds room temperature and a layer of oil floats. Among them, the top oil has high nutritional value, can protect gastric mucosa and has strong nourishing ability.