Macroalgae-derived hydrocolloids and their applications in food industry and their health effects

The growing global demand for sustainable food sources has intensified interest in macroalgae as an ecologically efficient and nutrient-rich biomass. Macroalgae are an important industrial source of hydrocolloids such as carrageenan, agar, alginate, ulvan, and fucoidan, which are widely used in the food, pharmaceutical, and cosmetic industries due to their gel-forming, thickening, and stabilizing properties. These polysaccharides exhibit not only outstanding techno-functional capabilities such as gel formation, thickening, stabilization, and viscosity europemodification, but also important biological activities such as antioxidant, anti-inflammatory, antimicrobial, and anticancer effects. Furthermore, the chemical composition and bioactivity of macroalgae vary significantly depending on the species, environment, and extraction conditions, which requires systematic comparisons and optimization. This review summarizes the chemistry of hydrocolloids derived from macroalgae, extraction techniques, structure-function interactions, and recent developments in their practical applications in food processing. Additionally, their bioactive properties, including antioxidant, antimicrobial, immunomodulatory, and metabolism-related effects, are evaluated from a health perspective based on current experimental data. This study specifically compares traditional and newly emerging extraction strategies and relates their technological-functional performance in food systems to their potential roles as health-promoting agents. In contrast to previous studies that typically emphasize technological applications or biological activity separately, this review synthesizes both perspectives to provide a comprehensive understanding of macroalgal hydrocolloids. This synthesis consolidates existing knowledge and establishes a perception-focused integrated framework that can guide future innovations in the development of next-generation food applications and advanced biomaterials.