What is "jeungpyeon"

Jeungpyeon is a variety of tteok ( Korean rice cake), made by steaming balls of fermented dough made from rice flour and rice wine such as makkeolli. It is one of the varieties of tteok that is typically served during the summer, because its sweet and sour taste is believed to be refreshing in hot weather, as well as to aid in digestion. While it is not certain that when people began to eat jeungpyeon, but there has been songhwa , a similar tteok made by fermentation since the Goryeo period.