【Reading】ちくよう

【English Name】Ranching

Chikuyo (holding culture) refers to a method of keeping and managing caught or imported seafood in pens, tidal flats, or aquaculture ponds for a certain period. Unlike yoshoku (aquaculture), which raises fish from the egg or juvenile stage, it is characterized by temporarily holding already-grown individuals to adjust the shipping timing and the quality of the flesh.

Among sushi toppings, the holding culture of bluefin tuna and yellowtail is widely known, and the difference in taste from wild fish often becomes a topic. On the other hand, in recent years what drew attention as a social problem was the origin fraud surrounding the holding culture of asari clams. A method of releasing imported clams from overseas into domestic shallows and tidal flats for a short period, then re-harvesting them and labeling them as domestic, had become routine. In January 2022, the media reported the reality that Chinese- and Korean-origin asari were being distributed as Kumamoto-grown or Ariake Sea-grown, and the Ministry of Agriculture, Forestry and Fisheries and Kumamoto Prefecture moved to correct it. There were also cases in which multiple businesses were cracked down on for origin fraud.

Holding culture itself is a legal method of fisheries management, but combined with the origin-labeling system it carries the risk of misleading consumers. In enjoying sushi as well, knowing the difference between wild, farmed, and held-culture fish can serve as a reference in choosing toppings.