Valorization of organic biomass through the production of active biopolymer film based on sodium caseinate, guar gum, and beeswax

The objective of the work was to study the impact of the inclusion of fennel (FEN) and coffee humic (COF) substances on the structure, physical and functional properties of composite materials based on sodium caseinate, guar gum, and beeswax. NMR results revealed the prevalent contribution of beeswax and caseinate suggesting a faster relaxation time (t1rH) in biopolymeric films. The active films obtained with COF contained more hydrophilic group than FEN film, which negatively impacted water vapor barrier properties. The optical properties of the films were influenced by the presence of aromatic rings in the extracts. Moreover, the presence of the humus extract reduced the elastic modulus (EM) as compared to neat films, due to reduced interactions between the polymeric chains. The active films containing fennel extract displayed better antioxidant and anti-microbial potential as compared to neat film with coffee husk extract suggesting an innovative sustainable formulation for food preservation.