Shelf life extension of Atlantic pomfret ( Brama brama ) fillets by packaging under a vacuum-skin system

Abstract

SUMMARYLipid damage produced during Atlantic pomfret (Brama brama) chilled storage (up to 19 days) was studied. For it, free fatty acid (FFA) and conjugated diene (CD) formation, peroxide value (PV), thiobarbituric acid reactive substances and fluorescent compounds formation were measured in two different white muscle zones (dorsal and ventral). Comparison with volatile amine formation (total volatile base-nitrogen, TVB-N; trimethylamine-nitrogen, TMA-N) was carried out. A gradual lipid hydrolysis was observed in both zones along the whole experiment. CD and peroxides formation was important during the experiment; peroxides showed the highest value at day 15 in both zones, that was followed by a peroxide breakdown at day 19. Interaction of oxidized lipids with nucleophilic compounds present in the fish muscle led to a gradual fluorescence development during the storage time in both zones. Mean values of the lipid content showed to be higher in the ventral zone than in the dorsal one, although significant differences could not be detected (p<0.05). Concerning the lipid damage, very small differences (p>0.05) could be assessed between both zones. TVB-N content showed no variation till day 15. At day 19, a sharp increase was observed for both muscle zones. In the case of TMA, a gradual increase was observed along the whole storage time for both muscle zones. Higher mean values were obtained in TVB-N and TMA-N indices for the ventral zone than for the dorsal one, according to a closer location to viscera where microorganisms are known to concentrate. Among the different indices tested for quality assessment, TMA-N and fluorescence formation were the most accurate for following the quality loss during Atlantic pomfret chilling, showing satisfactory (r 2 ≥0.87) non-linear fittings with the chilled storage time.2

The effects of modified atmosphere and vacuum packaging on quality of chub mackerel

“…The pH increases are in agreement with the findings of Erkan et al. (2001), Erkan (2003), Erkan & Mol (2004), Dhananjaya & Stroud (1994), Pérez‐Alonso et al. (2004) for chub mackerel, haddock, herring and Atlantic pomfret species stored in vacuum and in MAP.…”

“…The initial anaerobic sulphite‐reducing clostridia count was 1.48 log MPN g −1 for all samples whereas final counts were 4.04 log MPN g −1 for samples under both air and VP, 2.32 log MPN g −1 for samples under MAP. Similar anaerobic bacteria counts (4.80 log CFU g −1 ) have been reported for VP Atlantic pomfret fillets (Pérez‐Alonso et al. , 2004) and for iced cod (Jeyasekaran et al.…”

“…For MAP fish, it is well known that carbon dioxide can be absorbed into fish muscle surface, acidifying it via the formation of carbonic acid (Banks et al, 1980). The pH increases are in agreement with the findings of Erkan et al (2001), Erkan (2003), Erkan & Mol (2004), Dhananjaya & Stroud (1994), Pe´rez-Alonso et al (2004) for chub mackerel, haddock, herring and Atlantic pomfret species stored in vacuum and in MAP.…”

“…Initial bacterial population, gas/fish ratio and packaging materials are important factors affecting shelf life of fish in packages. Pérez‐Alonso et al. (2004) found initial aerobic and anaerobic bacterial counts as 4.52 and 2.76 log CFU g −1 in Atlantic pomfret fillets, respectively.…”

“…Erkan (2003) observed the spoilage of wrapped in cling film chub mackerel at 4 °C during the ninth day of storage. However, Pérez‐Alonso et al. (2004) observed that the loss of freshness and the onset of spoilage of Atlantic pomfret ( Brama brama ) fillets in traditional VP at 4 °C storage were on the seventh day and a control batch kept in air, 5 days of storage, respectively.…”