In life, some people consider "eating live fish" the best way to consume it. In fact, whether judged by nutritional value or taste, live fish or fish that has just died is not the optimal time for consumption.
Like other animals, after a fish dies, its muscle tissue continues to undergo biochemical reactions of rigor mortis, autolysis, and decomposition. During the rigor mortis stage, the proteins in the muscle tissue have not yet broken down into amino acids. When cooked at this time, the fish's flesh is relatively tough, not tender and fresh, and its nutrients are not easily absorbed by the body. After the fish's body has undergone high rigor mortis, it begins to transition into the autolysis stage. In this stage, the proteases in the fish's body gradually break down proteins into various amino acids that are easily absorbed by the human body. At this point, the fish flesh is tender and soft, and it is easy to digest and absorb after being eaten.
The transition of a fish from rigor mortis to autolysis depends on the environment, temperature, and time. The higher the external temperature, the shorter the time. Generally speaking, in summer, it can be cooked and eaten after being left for two to three hours, and in winter, after four to five hours. A fish at this stage will be incredibly delicious no matter how you cook it.