## 4 Discussion  
Fish producers, processors, and distributors work towards fisheries and aquaculture products supply to meet consumer demands. Herein, information on sensory, and microbiological changes, and more importantly on microbial communities' composition and VOCs profile, during chilled storage of the whole and filleted meagre from the Hellenic aquaculture, is highlighted for the first time, to help stakeholders provide products of a high-quality level in national and international commerce. In Greece, there are two more studies on quality characteristics of meagre, such as sensory, somatometric and chemical characteristics e.g., fatty acid profiles and volatile organic compounds, but this information only concerns the raw fish; meaning fish just after harvesting [4; 15]. These researchers have proved that meagre is a species that contains fat of high nutritional value and can give high fillet yield (42.2%). All these findings enhance the interest of stakeholders to produce large quantities of this kind of fish, and much more their interest to supply a high-quality food in commerce. Shell-life of fresh fish from the Mediterranean aquaculture, such as gilt-head seabram and European seabas, is usually ranged from 12 to 14 days for the whole fish in ice [13; 14], and from 5 to 6 days for their fillets stored at 4 \({}^{\circ}\)C [8; 17]. For meagre, shelf-life has been found to be 9 days for the whole and filleted fish in ice [6; 35]. However, in our case, the whole ice-stored fish was acceptable for human consumption until 12 and 15 days after catch, depending on the season of harvest. Fish shelf-life depends on the season since the mean water temperature in Greece differs approximately 10 or more degrees Celsius, between January and July. It is known that the water temperature can affect the population and composition of the bacteria present in seawater and fish [7; 36]. Moreover, the conditions wherein fish remains after catch (temperature in the aquaculture facilities until packaging in ice) and those wherein the products are distributed and marketed (air temperature in distribution and marketing after packaging in ice) strongly differ between winter and summer in Greece. Indeed, the initial TVC differed significantly between the whole meagre taken in January and July. In particular, fish caught in July \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Compound** & **ID 2** & **RI 3** & **Spearman’s** & **VIP** & **Boxplot 4** \\ \hline \(1\)-Pentanol & A & 1261 & \(-\)0.71 & 2.38 & \\ \hline \(1\)-Pentanol & A & 1261 & \(-\)0.71 & 2.38 & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: _Cont._presented TVC 2 log cfu/g higher than this observed for fish caught in January. Undericed storage conditions, TVC was at higher population levels in fish of July than those of January for the same time points during storage, reaching spoilage population levels of 7-8 log cfu/g three days earlier in fish of July than those of January. In the case of fish fillets, filleting can increase significantly the population levels of bacteria and change the microbial composition compared to the whole fish [8]. This means that the most important factor that determines the shelf-life of meagre fillets (7 days for fish of both months) differs from the factors that mainly affect the shelf-life of the whole meagre. The findings of the metabarcoding analysis revealed that, at the initial stage of storage, besides the presence of cosmopolitan bacteria belonging to the genera _Propionibacterium_, _Psychrobacter_ and _Sphingomonas_, which are commonly found in several fresh seafoods [37; 38; 39], _Clostridium_ was the most abundant bacterial group. However, it is crucial to point out that the microbial communities profile differed in whole fish from the two seasons during the whole storage period. More specifically, _Clostridium_ was the most abundant bacteria at D 3 in fish of July, while in fish of January, _Ralstonia_ and _Novosplingobium_ were found at higher abundances.