Development and Characterization of Brewer’s Spent Grain (BSG) Cellulose-Biopolymer Film

This thesis examines the valorisation of brewer’s spent grain (BSG) as a sustainable cellulose source for high-value products. Ultrasound was implemented to reduce reliance on strong chemicals in conventional alkaline treatment. The results showed enhanced delignification efficiency, achieving a cellulose recovery yield of 41.12%. The BSG-derived cellulose fibres were then processed into cellulose nanofibers (CNF) using high-pressure homogenization (HPH). The CNF functions as an effective reinforcing filler in sodium alginate biopolymer films, improving overall mechanical and barrier properties. This study contributes to the circular economy by converting underutilised BSG waste into a value-added material suitable for sustainable food packaging applications.