Fish waste accounts for almost one-third of the total fish production annually. The main objective of this study was to upcycle fish by-products to produce biodegradable packaging materials. Fish protein concentrate (FPC) was extracted from gilthead seabream by-catch (flesh and skin). FPC (3%) and gelatin (3%) were used to produce film-forming solutions. The films were produced according to the solvent casting method. The produced films were tested as packaging materials via the determination of different film properties. The wettability of the packaging materials was characterized based on the determination of the contact angle. Water vapor permeability was evaluated using the ASTM E96/E96M standardized method. The evaluation of mechanical properties was based on the Young’s modulus, tensile strength, and elongation at break. Color was measured using a CIELab system. The incorporation of FPC into the produced membranes resulted in a reduced contact angle from 108.5° to 90.6°; however, both films were characterized as hydrophobic materials. Films supplemented with FPC had lower tensile strength values compared to pure gelatin films, but higher elongation values without statistically significant differences. The color parameters (L,a,b) indicated that gelatin films and FPC–gelatin films were colorless and transparent (L > 90), an important parameter for food packaging materials. The production of biodegradable packaging materials from FPC and gelatin may effectively reduce petroleum-based plastics under the circular economy model.
The current study aimed to explore the effects of mild processing for shelf-life extension on the raw an-d cooked quality of gilthead seabream fillets stored at 2 °C. Control and Treated (via osmotic dehydration) fillets were sampled at the beginning (D1), middle (D5) and end (D7) of commercial shelf life. The raw quality was evaluated via the quality index method (QIM), microbial measurements and for D1 through tetrad discrimination testing. The cooked quality was evaluated for the same samples via sensory descriptive analyses with a trained panel. The tetrad results indicated similar characteristics between treatments for raw fillets on D1 and a 29% shelf-life extension for Treated fillets vs. the Control ones, defined by Quality Index Method and microbial measurements. The raw quality was reflected in the cooked quality of the tissue, with the Treated fillets exhibiting less intense spoilage-related sensory attributes as well as enhanced or retained freshness-related attributes throughout storage, when compared to the Control ones. A range of treatment induced sensory characteristics, partly associated to Maillard reactions, were developed in the Treated fillets. Overall, the treatment affected positively both the raw and cooked quality of the fillet, showing promising results as a shelf-life extension method for fish fillet preservation.
Plastic pollution has been recognized as an emerging risk for the aquatic environment. Shifting from the prevailing linear “take-make-dispose” model to a “circular” economy framework is essential for mitigating the environmental impact of plastics. Microplastics (MPs) in the natural environment are formed when synthetic polymers are fragmented and micronized to a size ≤ 5 mm. MPs are a global environmental problem, particularly within aquatic ecosystems, due to their persistence, accumulation, and uncertain long-term effects. This review examines the degradation pathways of polymers that result in MP formulation, their rate and distribution across ecosystems, and their potential entry into food systems. Key challenges include a lack of standardized detection methods, specifically for nanoparticles; limited evidence of long-term toxicity; and the inefficiency of current waste management frameworks. Emphasis is placed on the cradle-to-grave lifecycle of plastic materials, highlighting how poor design, excessive packaging, and inadequate post-consumer treatment contribute to MP release. The transition from Directive 94/62/EC to the new Regulation (EU) 2025/40 marks a significant policy shift towards stronger preventive measures. In line with the waste hierarchy and reduction in unnecessary packaging and plastic use, effective recycling must be supported by appropriate collection systems, improved separation processes, and citizen education to prevent waste and improve recycling rates to minimize the accumulation of MPs in the environment and reduce health impacts. This review identifies critical gaps in current knowledge and suggests crucial approaches in order to mitigate MP pollution and protect marine biodiversity and public health.