The results are presented in Figure 7 for the sodium hypochlorite-treated groups, as follows: Histatinase L and D exhibited a correlation with fish hardness and pH that was deemed to be highly significant ( p < 0.01), and histatinase B demonstrated a correlation with hardness and MFI that was considered to be significant ( p < 0.05).
It can be seen that histatinasease L activity showed an increasing trend at 2–3 d, that the rise was slow, probably due to the fact that histatinasease L and histatinasease B partially reacted with the same substrate, and that the elevation of histatinase B activity partially inhibited it; in the middle and late stages of refrigeration, the enzyme activity rose faster, which was due to the fact that, accompanied by the gradual decrease in the pH of the muscle tissues, lysosomes ruptured, and a large amount of histatinasease L was released [ 21 ].