Effect of salting procedures on quality of hake (Merluccius hubbsi) fillets

Abstract

The influence of salting procedures on the proximate analysis, mechanical parameters, and color of hake (Merluccius hubbsi) was investigated. Three procedures were comparatively evaluated: dry salting (DS), mixed salting (MS) and brining (BS). MS samples had the highest fat content, a considerable protein content and an equilibrium salt content similar to BS. MS samples had a great water loss, as DS method, but hardness and other mechanical parameters were similar to that obtained with BS, i.e. significantly lower than DS. All samples showed color parameters significantly different as compared to fresh hake, turning more red-orange as the salting time increased. Lightness diminished, a∗ values increased and b∗ values did not show a clear trend throughout the salting time. Principal component analysis (PCA) described the relationship between some variables (zNaCl, color, and mechanical parameters) with salting time. High Pearson's correlation coefficients were found between zNaCl and hardness, springiness, cohesiveness and a∗ parameter (r = 0.76, p < 0.001; r = 0.93, p < 0.0001; r = 0.95, p < 0.001 and r = 0.93, p < 0.0001, respectively). Luminosity was negatively correlated with zNaCl (r = -0.87, p = 0.0001). The correlation curves showed nonlinear relationships (R2adj between 83.7 % and 97.4 %), which could be used to predict quality attributes of hake fillets as a function of salting time. This work contributed to know the effect of different salting procedures on the quality attributes of a species widely available in the Southwest Atlantic Ocean.