Hantian Hantian, whose scientific name is agar, also known as agar, is called "Hantian jelly" in dessert shops. It is a seaweed polysaccharide extracted from natural seaweed plants. Crystal ball, generally called crystal ball, coconut or fruit. It is not harmful to the human body, but a large amount of sugar may be added during the production process, so it is recommended not to consume it in excess.