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Seafood or fish are a good source of high-quality protein, lipids, vitamins, and micro-elements, and are recognized to play a vital role in human health and nutrition (Ganguly et al., 2018). Seafood proteins are easily digestible and are rich in amino acids such as glutamic acid, aspartic acid, arginine, lysine, and leucine, some of which are deficient in cereal-based diets (Erkan & Özden, 2007). The consumption of marine fish is considered to have added benefits because of the presence of highly unsaturated fatty acids such as Eicosapentaenoic acid (EPA) and Docosahexaenoic acid (DHA) (Ganguly et al., 2018). These n-3 PUFA are shown to have several proven beneficial health effects against hypertension, inflammation, coronary heart disease, inflammatory and auto-immune disorders, and cancer (Darwesh et al., 2019;

This work describes the optimization of the pressure–time combination for the inactivation of Listeria monocytogenes in fish medium using a wide range of pressure (225–525 MPa) and holding time (5–30 min). Thereafter, the yellowfin seabream (Acanthopagrus arabicus) filets (100 g each) were subjected to high-pressure (HP) treatment at the optimum pressure/time combination, and the impact of HP on the amino acid profile, fatty acid profiles, color, and texture was assessed. Glycine, glutamic acid, and alanine were recorded as the major amino acids, which did not change significantly after pressurization. Conversely, alanine—the leading free amino acid—dropped significantly after treatment. The fatty acid analysis indicated that oleic acid and palmitic acid accounted for 29.88 and 25.59% of the total fatty acids, respectively. Pressurization did not influence the fatty acid profiles, nutritional quality indices, and hardness of yellowfin seabream fish. The color pigments of filets, measured as a* and b*, changed significantly after the treatment. Overall, this work indicates that HP treatment can be utilized to maintain the nutritional quality of seabream filets; however, further research is needed to maintain the visual color of the fish.

In the present study, the effect of enzymatic hydrolysis on the antioxidant activity of three red seaweeds (Chondria cornuta, Chondria dasyphylla, and Murrayella periclados) and two green seaweeds (Cladophora sp. and Ulva lactuca) from the Kuwait coast were evaluated. The seaweeds were hydrolyzed with five carbohydrases and three proteases, and the resulting extracts were tested for antioxidant activity. The total phenolic content and yield of the extracts varied greatly depending upon the species and enzyme used for hydrolysis. Of the 40 enzymatic extracts screened for antioxidant activity, the Viscozyme and Alcalase extracts of M. periclados, Neutrase and Ultraflo extracts of Cladophora sp., and Neutrase extracts of C. cornuta had high antioxidant activity compared to other enzymatic extracts in various in vitro assays. Fractionation of the extracts revealed that the radical scavenging and reducing power of the extracts were mainly due to phenolic fractions. In contrast, the iron‐chelating ability was mainly due to protein fractions. The level of prevention of lipid oxidation in the liposome model system varied for different fractions of extracts and did not correlate with total phenolic content and other antioxidant properties. The results of the study show that, by hydrolyzing seaweeds with specific enzymes, customized seaweed extracts with specific bioactivity could be obtained.

The objective of this study was to assess the quality parameters of hammour (Epinephelus coioides) fillets subjected to a high-pressure (HP) treatment at 375 MPa for 20 min followed by refrigerated storage for 30 days. The optimum pressure/time was selected based on the complete inactivation of Listeria monocytogenes. Treated samples were analyzed by amino acid profile, visual color, microstructure, and texture profile analysis. Lysine and glycine were the predominating essential and nonessential amino acids in hammour fillets. The total amino acids did not change by the HP-treatment, whereas the free amino acids decreased markedly from 4.35 to 2.43 mmol/g. The color of fillets changed significantly with the pressurization and storage in particular, a* and b* values. Hardness, compressibility, and adhesiveness increased after the HP-treatment. FTIR results indicated a shift in the amide II band after the HP-treatment and storage due to high-pressure-assisted protein denaturation. A porous structure was identified in the HP-treated microstructure of the fillet.The results indicated that HP-treatment could be successfully applied to hammour fillets for reduction of microbial growth with minor changes in quality. Industrial relevance:In recent days, the acceptability of high-pressure (HP) processing in the seafood industries is growing significantly. Hammour has a huge demand in the Middle Eastern countries for its exotic flavor and taste. An optimum pressure/time combination could maintain the desired flavor and safety of the fish fillets. Storage of highpressure-treated fillets, however, showed a decrease of the PUFA content significantly that needs to be further addressed. The obtained results could help the fish processing and service industries to boost the economy by providing pressurized hammour fillets.Novelty impact statement: High-pressure treatment retained the total amino acid contents and texture of hammour fish fillets. Retention of visual color/pigment remains the challenge of the process. | INTRODUC TI ONHammour (Epinephelus coioides), brown-spotted reef cod, is one of the most expensive seafoods in the Middle East because of its excellent nutritional profile and exotic flavor. The seafood consumption in the Middle East countries has increased steadily, and the per capita consumption is at par or above the world average of over 20 kg per capita per year (EU 2018; FAO, 2020). Because of the overfishing, poaching, and habitat destruction, the populations of the brownspotted grouper have declined significantly in recent years. Fisheries