High Pressure Processing (HPP) is a non-thermal technique of growing interest for fish preservation. In this work, the effect on functional properties of European hake (Merluccius merluccius) caused by HPP pre-treatment followed by freezing and frozen storage at-10ºC for 5 months were evaluated in an accelerated frozen storage study. Following a central composite design, five pressure levels (150, 169.27, 300, 430.73, or 450 MPa) and frozen storage times (0, 0.32, 2.5, 4.68, or 5 months) were tested. Colour parameters (L*, a* and b*) were measured in raw muscle. Expressible water and mechanical texture parameters were evaluated on both raw and cooked muscles. Results showed that a low-pressure level (150 MPa) allowed an adequate water holding capacity for raw muscle up to 2.5 months of frozen storage time. Values of 150 or 169.27 MPa did not cause significant changes on L* values of raw muscle when compared to nontreated samples. Overall, HPP led to changes on texture parameters of fresh muscle before and after cooking. However, 300 MPa and 5 months of frozen storage gave adhesiveness for raw muscle like that of non-treated fresh muscle. Moreover, 150-300 MPa for 5 months of frozen storage allowed cohesiveness and chewiness values for cooked muscle like those observed on cooked fresh hake showing that the HPP improves the quality of frozen hake. High-pressure processing before freezing and frozen storage of European hake (Merluccius merluccius): effect on mechanical properties and visual appearance