Summer's humidity and high temperatures make it tough to preserve food, and in the old days before refrigerators, people turned to seasonal ingredients to make them last.
They also made special snacks between meals that differ by season. One of them is rice wine cake called jeungpyeon, a summer treat. Made from ground rice and the traditional Korean rice wine makgeolli, it did not easily go bad even on hot summer days.
The sweet and sour taste is believed to originate from the Chinese rice cake called Sanghwa. In northern China, alcohol was added to flour and allowed to ferment as dough was kneaded and filling added.
The Korean version replaces hard-to-find flour with ground rice and adds a delicate garnish instead of filling.
Jeungpyeon is known by several names, including "sulddeok" (alcoholic rice cake) and "gijuddeok" (rice cake made by fermenting with alcohol).