【Reading】ちぬき

【English Name】Blood Draining

One of the elements that determines the quality of fish and shellfish used in sushi and sashimi is the removal of blood—known as chinuki (bloodletting). Deeply connected to both freshness and flavor, it is an indispensable technique in professional kitchens.

Blood remaining in the body of a fish oxidizes over time, producing a distinctive fishy odor. In addition, blood becomes a breeding ground for bacteria and a factor that accelerates the deterioration of the flesh. When bloodletting is performed properly, the flesh retains a beautiful, translucent color, which directly contributes to maintaining freshness.

The standard method is to insert the blade near the medulla oblongata or at the base of the tail during ike-jime (live slaughter) to drain the blood. Ike-jime itself originated in Japan in the early Edo period; by instantly destroying the brain and then quickly draining the blood, it became a traditional technique that enabled long-lasting freshness and has been passed down ever since.

In recent years, a hose-based bloodletting method named the Tsumoto method (Tsumoto-shiki) has attracted attention and gained wide support as a technique that enables long-term aging of fish.

The bloodletting procedure is also essential when preparing sujiko (salted salmon roe), which involves soaking the roe in roughly 2% saltwater while gently pressing it with the fingertips to remove the blood. It is a fundamental technique that determines the completeness of sushi toppings at the most basic level, and a point where a craftsman's skill is plainly revealed.