Su no shui is a traditional warm soup from Miyazaki Prefecture, made by simmering grated daikon (Japanese white radish) and iwashi (sardine) in vinegar and soy sauce. The word “shui” means “soup,” and the dish is also known locally as “sunshui” or “su no shiru.” It has long been served with mochi (rice cakes) during events like rice cake pounding.

Vinegar has been known since ancient times for its strong antibacterial properties and its ability to relieve fatigue. From the Edo period onward, rice vinegar began to be produced in large quantities and became widely used.

Iwashi is prepared in various ways, such as fillets or dumplings. The umami of the iwashi and daikon creates a simple yet deeply flavorful soup.