Comparative study of the nutritional composition of wild versus farmed yellowtail (Seriola lalandi)

The effect of chitosan (CS)-gallic acid (GA) conjugate (chitosan gallate, CS-g-GA) coating on the quality of silvery pomfret (Pampus argenteus) during refrigerated storage at 4 °C for 15 days was investigated. The total mesophilic and psychrotrophic microbes in control and coated fish samples were counted periodically; physicochemical analyses to determine pH, total volatile basic nitrogen (TVB-N), peroxide value (POV), thiobarbituric acid-reactive substances (TBARS), K-value, and water-holding capacity (WHC) were carried out; and sensory attributes were evaluated. The results indicated that both CS + GA and CS-g-GA coatings effectively preserved the silvery pomfret quality during refrigerated storage. However, CS-g-GA had higher antimicrobial activity and a better ability to inhibit the formation of volatile bases (TVB-N) and lipid oxidation products (POV and TBARS) as well as the degradation of ATP and its breakdown products (K value) than CS + GA during the storage period. Furthermore, the CS-g-GA coating also helped to maintain a higher WHC and had better sensory properties for a longer period of time compared to the other treated samples, thus extending the shelf life and delaying the deterioration of fresh silvery pomfret by 3–6 days during refrigerated storage. These results suggest that a CS-g-GA coating could be employed as an active packaging material in the fish preservation industry.

Effect of Chitosan Gallate Coating on the Quality Maintenance of Refrigerated (4 °C) Silver Pomfret ( Pampus argentus )

The aim of this study was to determine the differences in the nutritional properties of wild and cultured loach Misgurnus anguillicaudatus obtained from southern Japan. Major parameters, such as whole-body proximate composition, lipid classes, and fatty acid and amino acid composition, were investigated. The whole-body total lipid content of cultured loach was twofold higher than that of wild loach and the proportion of neutral lipids was significantly higher in cultured loach than in wild loach. However, the polar lipid content was two- to threefold lower in cultured loach than in wild loach. Compared to the wild loach, higher contents of 20:5n-3 and 22:6n-3 were detected in cultured loach, but much lower contents of 20:4n-6. In terms of whole-body amino acid composition, wild and cultured loach showed similar profiles. In conclusion, the consumption of cultured loach will contribute to dietary n-3 highly unsaturated fatty acids intake, with a benefit to human health.

Comparative studies on lipid profiles and amino acid composition of wild and cultured Dojo loach Misgurnus anguillicaudatus obtained from southern Japan

The present literature overview was carried out in order to assess the use of fatty acids (FA) analysis in fish farming research during the last decade. As aquaculture products are mainly intended for human consumption, the overview is focused on fish fillet, carcass or whole body FA, as a major aspect of fish nutritional value. This survey used 394 papers and demonstrated that a) 71% of papers report FA as relative percentage of total FA (% totFA), b) 23% of papers report actual FA amounts, c) in 63% of papers not enough information is provided in âMaterials and Methodsâ section to understand exactly how FA analysis was performed, and d) based on FA percentages, results are not always the same as when based on FA amounts, and thus divergent conclusions about treatment effects could be drawn. These findings indicate that certain issues need to be addressed regarding adequate description of analytical methods followed for FA analysis, presentation and interpretation of FA results and may help to highlight critical points that should be considered from the researchers' and scientific journals' sides in order to foster more informative research publications.

An Overview of the Use of Fatty Acids in Fish Farming Research during the Last Decade, with Particular Emphasis on Fish Quality

This study investigated the effects of varying dietary levels of decosahexaenoic acid (DHA) on growth performance, proximate composition and whole body fatty acid profiles of juvenile silver pomfret, Pampus argenteus. Triplicate groups of fish (30.55 ± 0.08 g) were fed diets containing 5.2%, 9.31% and 13.38% DHA (% of total fatty acids) or 0.85%, 1.52% and 2.18% DHA on dry diet weight for diets 1, 2 and 3 respectively. Survival was not affected by dietary DHA levels. The growth performance and feed utilization parameters of fish fed diets 2 and 3 were significantly (P   0.05). Whole body lipid and fatty acid profiles were influenced by dietary DHA levels. Significantly higher n-3 fatty acids particularly DHA, DHA:EPA(eicosapentaenoic acid) ratios and n-3:n-6 ratios were observed in fish fed diets 2 and 3 compared to those fed diet 1. Better growth performance and higher whole body DHA:EPA (2.31, 2.29) ratios and n-3:n-6 ratios (2.17, 2.12) observed in fish fed diets 2 and 3, respectively, suggests that silver pomfret juveniles have a higher requirement for n-3 fatty acids, notably DHA for optimum growth and survival.

Effects of varying dietary docosahexaenoic acid levels on growth, proximate composition and tissue fatty acid profile of juvenile silver pomfrets, Pampus argenteus (Euphrasen, 1788)

We evaluated the biochemical composition of juvenile cultured and wild silver pomfret Pampus argenteus. Cultured silver pomfret (SF) had significantly (P < 0.05) lower crude protein content and higher crude lipid content than wild SF. Concentrations of almost all amino acids, except glycine and arginine, were significantly higher (P < 0.05) in wild SF compared to cultured SF. Further, wild SF had a significantly (P < 0.05) higher concentration of total amino acids (TAA), essential amino acids (EAA), and a higher essential amino acid index (EAAI) than cultured SF. Saturated fatty acids (SFA) in cultured SF were significantly higher than in wild SF. However, the content of poly-unsaturated fatty acids (PUFA) and n-3 fatty acids in wild SF was significantly higher than in cultured SF. Mono-unsaturated fatty acids (MUFA) in cultured and wild SF were not significantly different. Fatty acids C16:0 and C18:1 were the principal fatty acids of the SFAs and MUFAs, respectively, in both cultured and wild SF. The results will be useful for determining the dietary requirements for culture of SF.

Zhaohong Shi

Papers

Biochemical composition of juvenile cultured vs. wild silver pomfret, Pampus argenteus: determining the diet for cultured fish.