Effect of slurry ice on chemical changes related to quality loss during European Hake ( Merluccius merluccius ) chilled storage

Abstract

Slurry ice is a biphasic system consisting of small spherical ice crystals surrounded by seawater at subzero temperature. Its employment was evaluated in the present work as a new chilled storage method for whole European hake (Merluccius merluccius) and compared to traditional flake icing. Different chemical analyses (nucleotide degradation, formaldehyde formation, lipid hydrolysis and oxidation, interaction compounds formation and electrophoretic protein profiles) related to quality changes were analysed and compared to sensory evaluation. An inhibitory effect on quality loss mechanisms was observed for the slurry ice treatment, according to nucleotide degradation (K value), free formaldehyde content, browning development and sarcoplasmic protein profiles. No differences in lipid hydrolysis and oxidation could be outlined by comparison between both icing conditions. The sensory analysis showed a higher shelf-life time for slurry icing than flake icing (12 days and 5 days, respectively). Results confirm the practical advantages of using slurry ice as a chilling storage method.

Preservative effect of an organic acid‐icing system on chilled fish lipids

“…However, in the case of PV and TBA-i, some decreases in advanced chilled stages (days 12 and 15) could also be observed; such decreases can be explained on the basis of the high reactivity of molecules to be measured under both quality indices [25,32]. As a result, the best correlation values between chilling time and lipid oxidation development could be observed when considering the FR assessment (r 2 ¼ 0.82-0.87), also in agreement to previous research [30].…”

“…Such a result has already been observed in previous research in chilled lean fish species [25,30] and proves a strong connexion between lipid hydrolysis and oxidation. In this sense, a FFA pro-oxidant effect has been explained on the basis of a catalytic effect of the carboxyl group on the formation of free radicals by the decomposition of hydroperoxides [38].…”

“…However, no inhibitory effect ( p>0.05) could be observed as a result of employing ice including a 400 ppm concentration of the organic acid-mixture. As in previous research [30], lipid hydrolysis development in chilled hake provided an increasing tendency with chilling time in all icing conditions, so that a good correlation value was obtained between both parameters (r 2 ¼ 0.93-0.95, quadratic fitting). A similar result could be concluded for megrim fish (Fig.…”

“…Taking into account the peroxide (lower scores than 5.0 in all cases) and the TBARS (lower scores than 0.9 in all cases) values, hake lipid oxidation can be considered low in all kinds of fish samples, according to previous research concerning chilled storage of this species [29,30]. In general terms, increasing values could be observed with time in all kinds of samples for the different quality indices.…”

Comparative evaluation of the quality changes in Squid (Ommastrephes bartrami) during flake and slurry ice storage

“…3). The absorption of NaCl into the fish during the storage period in slurry ice was found to be slow Rodríguez et al, 2008;Losada et al, 2004). The increasing in salinity can enhance the water holding capacity and inhibit the growth of microbial during the storage period of marine species (Lei Y. et al, 2007).…”