Physicochemical Characterisation of Polysaccharide Films with Embedded Bioactive Substances

Area of Science:

• Materials Science
• Polymer Science
• Food Science

Background:

• Biodegradable films are crucial for sustainable food packaging.
• Sodium carboxymethyl cellulose (CMCNa) is a promising biopolymer for film development.
• Citric acid (CA) is a safe and effective crosslinking agent for biopolymers.

Purpose of the Study:

• To prepare and characterize CMCNa bioactive films crosslinked with CA for food packaging applications.
• To evaluate the physical, mechanical, thermal, and antioxidant properties of the developed films.
• To assess the potential of these films in enhancing food product shelf life and safety.

Main Methods:

• Preparation of CMCNa films crosslinked with varying concentrations of CA.
• Characterization of film properties including thickness, transparency, moisture content, moisture absorption, and barrier properties.
• Assessment of mechanical strength (tensile strength, elongation at break) and thermal stability (thermogravimetric analysis).
• Evaluation of antioxidant activity under different conditions (temperature, solubility).

Main Results:

• Films exhibited suitable thickness, transparency, and moisture content for packaging.
• Excellent moisture absorption and barrier properties were observed, linked to CMCNa concentration and CA crosslinking.
• Mechanical strength was not significantly affected by crosslinking or bioactive components.
• Crosslinking slightly improved thermal stability.
• Antioxidant activity varied with temperature and solubility, indicating tunable functionality.

Conclusions:

• Crosslinked CMCNa bioactive films possess desirable properties for food packaging.
• These films offer potential for controlled release of bioactive components, extending food shelf life.
• The developed materials contribute to the advancement of functional and biodegradable food packaging solutions.