Correlation Between Electrical Conductivity of the Gutted Fish Body and the Quality of Bighead Carp (Aristichthys nobilis) Heads Stored at 0 and 3 °C

The changes in impedance change ratio (Q value), pH value, texture, K value, total volatile basic nitrogen (TVB-N), total aerobic count (TAC), drip loss, and sensory assessment (SA) of bighead carp (Aristichthys nobilis) during 0 and 3 °C storage were investigated. Simultaneously, correlation models were developed by analyzing the correlation between the measured values. The results indicate that during postmortem storage, Q value is significantly (p?<?0.05) related to pH value and texture indexes (hardness, adhesiveness, springiness, cohesiveness, and resilience); during long-term storage, SA exceeds the acceptable limit on the 15th day at 0 °C and the 12th day at 3 °C, while K value, TVB-N, TAC, and drip loss increase to 72.4 %, 18.9 mg/100 g, 4.82 log₁₀ cfu/g, and 7.09 % at 0 °C, and 78.5 %, 14.0 mg/100 g, 4.97 log₁₀ cfu/g, and 5.08 % at 3 °C, respectively. Meanwhile, Q value declines to 18.9 % at 0 °C and 12.7 % at 3 °C. The correlation coefficients between Q and K values, TVB-N, TAC, drip loss, and SA are 0.955, 0.964, 0.966, 0.965, and 0.994 at 0 °C, and 0.969, 0.967, 0.979, 0.960, and 0.996 at 3 °C, respectively, indicating significant linear relationships (p?<?0.05). Therefore, Q value can be used as a fast nondestructive method to estimate the quality of bighead carp heads during storage at 0 and 3 °C.