Evaluation of different methods of stunning/killing sea bass (Dicentrarchus labrax) by tissue stress/quality indicators.

The aim of the study was to evaluate the effect on the final product quality of certain innovative stunning/killing methods for sea bass as substitutes for the most common methods used by European farmers. The changes in tissue stress/quality parameters were monitored from the first hours after death and during the shelf life of the fish. Two trials were conducted in July and November on n. 231 sea bass stunned/killed by ice-water slurry, by single gas or mixture of gases in ice-water and by single- or two-stage electrical stunning/killing methods. Behavioural responses, stun/death time, rigor index, muscular and ocular pH, lactic acid, ATP and catabolites at death and within the 24 h after death were determined. In the November trial, the sensorial evaluation, rigor index, IMP, inosine, hypoxanthine, and K1 values were also evaluated during refrigerated storage until spoilage. The stunning/killing in ice-water appeared to induce low effects on the analysed parameters and preserve a good product quality as indicated by the highest pH and ATP values at death, the delayed full rigor onset and the 1 day longer shelf life (14 days) in comparison with the single- or two-stage electrical stunning/killing. The gas mixture addition provided a 40 % shortening of the time to obtain stunning/killing and 14 days of shelf life. The actual level of quality loss with the different killing conditions and the actual impact of a significant shortage of rigor mortis onset and pH drop on the possible pre-rigor filleting remain to be studied in depth.

The atherosclerotic risk profile is affected differently by fish flesh with a similar EPA and DHA content but different n-6/n-3 ratio.

The aim of this study was to evaluate the effect of consuming gilthead sea bream fillets, with different n-6/ n-3 ratios, on atherosclerotic biomarkers. Twenty healthy subjects were included in a randomised single-blinded cross-over trial. Participants were randomized into 2 groups, both of which received approximately 630 g per week of gilthead sea bream fed with either 100% fishmeal (FM) or partial replacement with plant proteins (PP) over two consecutive 10 week periods, respectively. Group A consumed firstly the FM fillets followed by the PP fillets, whereas the reverse order was adopted for group B. Group A reported a significant decrease of 29.3% (Δ = -26 mg/dL) in total cholesterol after the first phase of the intervention, before returning to baseline levels after the dietary intervention with fish fed with PP. Similarly, in group A, both LDL-cholesterol and triglycerides decreased significantly by 21.6% (Δ = -19 mg/dL) and 11.7% (Δ = -10.7 mg/dL), respectively, before increasing again after the intervention. Improvements in the inflammatory cytokines, interleukin-6 and -8 were also noted. Moreover, whole blood viscosity appeared significantly improved in group A, as seen by a significant increase of 7.59% (Δ = +4.59 mPA) for erythrocyte filtration rate. In conclusion, similar EPA+DHA content with different n- 6/n-3 ratio fish flesh intake was shown to have varied affects on lipid, inflammatory and haemorheological parameters in a group of healthy subjects.

WEFTA interlaboratory comparison on total lipid determination in fishery products using the Smedes method.

Lipid determination by the Smedes method was tested in an interlaboratory trial performed by nine laboratories from seven countries belonging to the West European Fish Technologists Association Analytical Methods Working Group. Five samples of fish and fishery products with different lipid contents, including two blind duplicates, were distributed among the participants. All laboratories applied a slightly modified Smedes method, which included extraction of lipids by cyclohexane and isopropanol, transfer of lipids to the cyclohexane phase by addition of water, phase separation by centrifugation, and gravimetric lipid determination. The results indicate that the RSD for reproducibility (RSD(R)) was between 4.11 and 6.31% for samples with moderate (7%) and high (14%) lipid content, depending on the sample. Larger SDs among the laboratories were obtained for a cod sample with low lipid content of 0.5%. The method is judged to be suitable as a routine method for lipid determination in fish and fishery products.

Lipid, inflammatory and haemorheological profiles are significantly affected by farmed fish eating: an intervention study.

AIM: The objective of the present study was to evaluate the influence of short-term dietary intake of farmed fish on biomarkers related to the atherosclerotic process. METHODS AND RESULTS: Lipid, inflammatory, and haemorheological variables before (T0) and after a dietary intervention with about 800 g Orbetello farmed sea bass per week for 10 weeks (T1) were evaluated in nine dyslipidemic subjects. Fish intake significantly decreased triacylglycerols (T1, 140.2+/-20.3 mg/dl versus T0, 183.3+/-29.2 mg/dl; P =0.04), whereas no significant changes for the other lipid variables have been observed. Moreover, dietary intervention significantly (P <0.05) decreased all of the inflammatory parameters investigated; namely, high-sensitivity C-reactive protein, interleukin-6, and interleukin-8. Furthermore, a significant (P =0.04) improvement in erythrocytes' deformability index was reported after 10 weeks of fish dietary intake (9.0+/-0.7% versus 5.4+/-1.0% for T1 and T0, respectively). CONCLUSION: Dietary short-term intake of farmed fish seems to impose favourable biochemical changes in dyslipidemic subjects.