Sustainable Extraction of Bioactive Compounds from Food Processing By-Products: Strategies and Circular Economy Insights

The rising amount of food industry waste has sparked interest in its valorization as a source of bioactive compounds. This study combines bibliometric analysis and a systematic review to map the scientific literature on the recovery of bioactive compounds from food byproducts, focusing on green extraction strategies and their alignment with the principles of the circular economy. A total of 176 documents, published between 2015 and 2025, were analyzed. The analysis shows significant growth after 2020 and highlights bioactive compounds, extraction, and the circular economy as the primary research themes. Italy, Spain, and Brazil emerged as the leading countries in scientific production. The systematic review covers green extraction techniques, including ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), pressurized liquid extraction (PLE), supercritical fluid extraction (SFE), enzyme-assisted extraction (EAE), and natural deep eutectic solvent extraction (NADES). UAE- and NADES-based processes were the most frequently applied extraction techniques, mainly targeting phenolic compounds and flavonoids. Significant progress has been observed, particularly in the advancement of extraction technologies, in the recovery of key bioactive compounds, and in their industrial applications. These methods recover phenolics, flavonoids, anthocyanins, and other compounds with antioxidant, antimicrobial, and cardioprotective properties, which have potential applications in functional foods, nutraceuticals, pharmaceuticals, cosmetics, and biodegradable packaging. Nutraceuticals and functional foods represent the main application areas, followed by cosmetics and pharmaceuticals. Despite progress, challenges remain, including scalability, equipment costs, solvent recovery, and process standardization. The green extraction of bioactive compounds from food byproducts shows promise and can support the goals of the 2030 Agenda.