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.

Automated summary

The study examined the effects of fennel and coffee humic substances on the properties of composite materials made with sodium caseinate, guar gum, and beeswax. The results showed that the active films with coffee humic substances had more hydrophilic groups but worse water vapor barrier properties compared to fennel films. The presence of aromatic rings in the extracts affected the optical properties of the films, and the addition of humus extract reduced the elasticity of the films.