Water chestnut (Trapa japonica) once commonly grew in the rice paddies, marshes and ponds of the flatlands of Sintaein-eup. The fruit would be harvested in October, when it also provided a food source to swans and other water birds returning to the area, and used to make mareummuk. Mareummuk is made by rinsing powdered water chestnut and collecting the sediment, which is boiled and cooled until it hardens into a jelly. Today, many rice paddies in Sintaein-eup been turned in ponds specifically to cultivate the water chestnut.
“Mareum” in Korean means “a water plant which bears large appetizing fruit,” and this nutritious plant has been used as a food source for over 500 years. The water chestnut was documented in Korea as far back as the 16th century. The jelly made from water chestnuts is not sold commercially, but made for personal or family consumption in southwestern Korea. However, after the land consolidation in the 1970s, the natural habitat of the plant disappeared causing memories about mareummuk to disappear from the minds of people as well.