Color, Structure, and Thermal Stability of Alginate Films with Raspberry and/or Black Currant Seed Oils

Area of Science:

• Materials Science
• Food Science
• Polymer Science

Background:

• Sodium alginate films are explored for food packaging due to their biodegradability.
• Fruit seed oils contain bioactive compounds with potential for active packaging applications.
• Current food packaging materials often lack biodegradability and active functionalities.

Purpose of the Study:

• To develop biodegradable and active films from sodium alginate incorporated with fruit seed oils (raspberry seed oil and black currant seed oil).
• To characterize the color, structure, and thermal stability of the developed active films.
• To evaluate the potential of these films for food packaging applications.

Main Methods:

• Sodium alginate films were prepared with 25% and 50% concentrations of raspberry seed oil (RSO) and black currant seed oil (BCSO).
• UV-VIS spectroscopy was used to analyze bioactive compounds in the oils.
• Color (CIELab), structure (SEM), and thermal stability (thermogravimetric analysis) were evaluated.

Main Results:

• The addition of RSO and BCSO significantly increased the yellowness of the alginate films.
• SEM analysis revealed differences in surface morphology and internal structure, with RSO films showing more developed surfaces and distributed holes.
• Thermogravimetric analysis indicated that the oils reduced the efficiency of alginate decomposition in the initial stage, enhancing thermal stability.

Conclusions:

• Biodegradable and active food packaging films can be successfully produced using sodium alginate and fruit seed oils.
• The developed films possess functional properties, including enhanced thermal stability and consumer-acceptable visual characteristics.
• Utilizing fruit seed residues for active packaging offers a sustainable approach to food preservation.