Optimization of common carp pre-slaughter by using TBA index and Response Surface Methodology (RSM)

The quality of fish flesh is affected by several factors including slaughtering methods and pre-slaughter conditions. In this study the effect of main operational variables such as fasting time (Xt), density  (Xn) and fish weight  (Xw) in the TBA value of common carp fillet has been evaluated and analyzed using the response surface method and Box-Behnken model. A numerical optimization model was performed to obtain the minimum amount of TBA in the fillets. Adapted fish treated by fasting time, density and weight and then harvested after 1, 4 and 7 days, slaughtered by smothering out of water and then fillet. The results showed that the lowest TBA value on the second-order model was obtained at low level of  (Xn) (4 fish numbers), low level of  (Xw) (500 g) and high levels of  (Xt) (7 days fasting time). The optimal TBA value was determined 0.6842 by model which was measured 0.701 after the practical validation test in optimal condition which indicating the high accuracy of the model to determine the optimum pre-slaughter. Therefore, the results of this study showed that using the response surface method is appropriate to optimize pre-slaughter conditions of common carp and also the second-order model can be used to predict the response variable in difference conditions of pre-slaughter.