There are two common kinds of grass jelly in Vietnam which are Mesona chinensis (called sương sáo in Vietnamese) and Tiliacora triandra (called sương sâm; sương sa or rau câu is the name for jelly made from various kinds of algae).
The sour flavour of the soup comes from the use of tamarind (អម្ពិល) and certain tangy vegetables such as tomato (ប៉េងប៉ោះ) and pineapple (ម្នាស់), as well as Tiliacora triandra leaves (ស្លឹកវល្លិយាវ).