Abstract

Among the different recent technologies to be applied for marine food preservation, hydrostatic high pressure (HHP) processing has attracted great attention. HHP has shown to be profitable by inactivating microbial and endogenous enzyme activities; however, deteriorative problems have been encountered with chemical constituents, these leading to marked quality losses related to the general appearance of the product and a consumer acceptance lowering. The present work was focused on the sensory and physical changes of chilled fish that was previously treated with HHP technology. For it, farmed coho salmon (Oncorhynchus kisutch) was chosen, because of its increasing farming production and commercial interest. As previous treatment, three different HHP conditions (135 MPa-30 s; 170 MPa-30 s; 200 MPa-30 s; treatments T1, T2 and T3, respectively) were tested and compared to untreated fish (control). Sensory (rancid, amine, typical and putrid odours, colour, general aspect, hardness, cohesivity) and physical (gaping, firmness, deformation and colour) parameters were analysed on chilled muscle after 0, 6, 10, 15 and 20 days of storage. A 2 2 fractional factorial design was applied to identify the significant (p<0.05) variables of the HHP process. Comparison among conditions showed that control and T1 batches provided lower variations in sensory and physical properties (namely, lightness and rancidity and putrid odours) than the two other HHP conditions; indeed, the best gaping degree retention was observed in fish previously treated under T1 condition. It is concluded that T1 condition followed by chilled storage can provide an effective combination to maintain sensory and physical properties of chilled fish.