SUSTAINABLE STRATEGIES TO ENHANCE THE EXTRACTION, FUNCTIONALITY AND NUTRITIONAL QUALITY OF PROTEINS FROM PALMARIA PALMATA

Abstract

This thesis explores enhanced protein extraction methods from Palmaria palmata and examines the extracted proteins’ techno-functional and nutritional properties. Among various pretreatments, microwave digestion (MD-500 W, 30 min) and acid hydrolysis (AH-2 M H₂SO₄, 95 ºC, 2 h) increased extraction yield from 10.4±0.4% to 47.6±3.9% and 46.5±3.4%, and protein purity to 89.8±1.1%, and 65.3±1.2% respectively, compared to conventional alkaline solubilization and acidic precipitation (p < 0.05). MD and AH treatments improved in vitro protein digestibility from 6.3±0.8% to 11.6±0.8% and 14.4±0.7%, enhanced emulsifying activity from 0.31±0.01 to 0.93±0.05 and 0.87±0.02, and increased fat-holding capacity by 12.9% and 3.2%, respectively (p < 0.05). These pretreatments disrupted cell walls, reduced particle size and protein molecular weights, and increased flexibility and unfolding. The study demonstrated that MD and AH pretreatments are efficient, sustainable methods for converting red seaweed proteins into viable alternative protein sources, thereby enhancing the sustainability of global food systems.