Quality predictive models of grass carp (Ctenopharyngodon idellus) at different temperatures during storage

To study quality changes in cold chain circulation, kinetic models were developed to predict the freshness changes of grass carp at different temperatures during storage. Sensory assessment, total aerobic count (TAC), K value, total volatile basic nitrogen (TVB-N) and 2-Thiobarbituric acid (TBA) at −3, 0, 3, 9 and 15 °C were accessed to investigate the relation between the freshness changes and temperature. The kinetic models of sensory assessment, TAC, K value, TVB-N and TBA with respect to storage time and temperature were developed based on Arrhenius equation. The high regression coefficients (R2 > 0.9) indicated the acceptability of the first-order reaction and Arrhenius model for predicting the quality changes of grass carp. Activation energies (EA) of sensory assessment, TAC, K value, TVB-N and TBA are 114.38, 75.88, 57.11, 111.55, 63.09 kJ mol−1, and corresponding rate constants (k0) are 2.97 × 1020, 1.12 × 1013, 8.30 × 109, 8.34 × 1019, 9.06 × 1010 respectively. Relative errors between predicted and observed freshness indictors values of TAC, K value and TVB-N are all within ±10%. Therefore the quality changes of grass carp can be predicted based on the prediction model of TAC, K value and TVB-N within −3-15 °C.