The Mediterranean area is one of the major global producers of agricultural food. However, along the entire supply chain—from farming to food distribution and consumption—food waste represents a significant fraction. Additionally, plant waste residues generated during the cultivation of specific fruits and vegetables must also be considered. This heterogeneous biomass is a valuable source of bioactive compounds and materials that can be transformed into high-performance functional products. By analyzing technical and scientific literature, this review identifies extraction, composite production, and bioconversion as the main strategies for valorizing agricultural by-products and waste. The advantages of these approaches as well as efficiency gains through digitalization are discussed, along with their potential applications in the Mediterranean region to support new research activities and bioeconomic initiatives. Moreover, the review highlights the challenges and disadvantages associated with waste valorization, providing a critical comparison of different studies to offer a comprehensive perspective on the topic. The objective of this review is to evaluate the potential of agricultural waste valorization, identifying effective strategies while also considering their limitations, to contribute to the development of sustainable and innovative solutions in Mediterranean bioeconomy.

The present study aimed to evaluate the changes in extra virgin olive oil (EVOO) after enrichment treatments with Thymus leptobotrys, a Moroccan endemic aromatic plant. The EVOO sample was supplemented with two materials obtained from the aerial parts of T. leptobotrys: powder (2.5 and 5) or essential oil (100 and 200ppm). The chemical composition analysis of T. leptobotrys extracts (essential oil and powder methanolic extract) allowed the determination of its phenolic profile. Quality parameters (acidity, peroxide value, and specific extinction coefficients), color, fatty acids composition, minor components (pigments and phenol), and Rancimat oxidative stability of the control and enriched oils were measured. Rosmarinic acid and thymusin were the main identified compounds in the powder; thymusin was identified for the first time in the essential oil where it was predominant. Generally, the enrichments did not downgrade the oil from its initial category (EVOO), according to quality indexes. Adding T. leptobotrys to EVOO, especially the essential oil, enriched its phenolic profile by allowing the migration of thymusin, a lipophile flavone, without affecting its quality parameters or color.

Bio-based and biodegradable polymer composites based on polylactic acid (PLA) and polybutylene succinate-co-adipate (PBSA) were developed for rigid food packaging applications. Agro-industrial residues consisting of ground leaves and branches derived from tangerine tree cultivation (pruning) were used as fillers at high loading (30 wt%) before (PRE) or after (POST) extraction of bioactive compounds. The influence of blend composition (PLA/PBSA 60/40 and 30/70), filler extraction, and the addition of antioxidants (0.5 wt%) on material properties was systematically investigated. Composites were processed via extrusion and injection molding and characterized through FTIR, SEM, tensile testing and thermal analysis. The results show that polymer blend morphology affects mechanical behavior, with co-continuous structures (60/40) exhibiting improved ductility compared to dispersed systems (30/70). The incorporation of lignocellulosic residues increased stiffness but reduced elongation at break. Extraction treatment significantly modified filler morphology and interfacial interactions, slightly improving dispersion and processability. The effect of the extracted bioactive compounds on the thermal stabilization of biocomposites was also investigated. Overall, the findings demonstrate the potential of combining biodegradable polymer blends with treated agricultural residues to produce sustainable rigid packaging materials while supporting a bio-circular approach. In fact, preliminary extraction of valuable compounds from tangerine pruning waste appears to be a convenient strategy for its efficient cascade valorization.

Polyelectrolyte complexes (PECs) are recognized as promising materials for the development of sustainable food packaging. In this study, eco-friendly PECs based on pectin (P) and chitosan (C) were prepared by solvent casting at different pH values and volume ratios (C, P, 1C:1P, 1C:2.5P, and 1C:5P) (v/v). The resulting films were characterized for numerous features, including thickness, opacity, moisture content, swelling degree, and water solubility, while mechanical performance (elongation at break and tensile strength), water vapor transmission rate (WVTR), surface energy, and anti-adhesive activity were evaluated for the most promising formulation. The results revealed that blending chitosan with pectin significantly improved the films’ physicochemical properties, notably by increasing thickness (up to 100 µm) and opacity (slightly above 2) while reducing the swelling degree (from over 1800% for pure chitosan to below 600% for 1C:2.5P film at pH 3.2) and the water solubility (from 100% for pectin films to around 45–50% for the blended films). The film 1C:2.5P at pH 3.2 showed improved barrier performance, with a lower WVTR (approximately 20 g/h·m²) compared to the single polymer films (more than 30 g/h·m²), and exhibited significant anti-adhesive activity by reducing bacterial adhesion to below 5% compared to 65% for the conventional packaging film. However, these improvements were accompanied by reduced tensile strength (From ~4.2 MPa to ~1.3 MPa) and in elongation at break (from ~50% to ~20%). Overall, PEC films demonstrate strong potential as sustainable packaging materials by combining improved barrier properties and anti-adhesive activity, despite some limitations in mechanical resistance.