PSI - Issue 68

ScienceDirect Structural Integrity Procedia 00 (2025) 000–000 Structural Integrity Procedia 00 (2025) 000–000 Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Available online at www.sciencedirect.com ScienceDirect

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

Procedia Structural Integrity 68 (2025) 845–853

European Conference on Fracture 2024 Structure and mechanical properties of biopolymer films with incorporated tea tree essential oil Krastena Nikolova a *, Maria Marudova b , Alexander Pashev c , Sofia Milenkova b , Anelia Gerasimova а European Conference on Fracture 2024 Structure and mechanical properties of biopolymer films with incorporated tea tree essential oil Krastena Nikolova a *, Maria Marudova b , Alexander Pashev c , Sofia Milenkova b , Anelia Gerasimova а Abstract Polysaccharide films with essential oil of tea tree ( Melaleuca alternifolia ) with a concentration of 1% were developed by casting and evaporation of the solvent. To improve the mechanical properties of the films, plasticizer glycerol was added. The intermolecular interactions of polysaccharides and essential oil were evaluated, and for this purpose, the infrared spectra were taken using Fourier transformation. Film surface was examined using an electron scanning microscope. Data were obtained on the mechanical properties of the films, such as deformation, strength, and modulus of elasticity. The research results confirm the potential for incorporating essential oils into the polysaccharide matrix for food applications as edible films. © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ECF24 organizers Keywords: chitosan, pectin, HPMC, alginate, edible films, tea tree oil 1. Introduction Edible biopolymers and food-grade ingredients are commonly utilized to create edible films and coatings. Edible films are defined as thin layers of consumable material applied as a protective covering on food items, and they can be eaten along with the product itself (Galus et al., 2020). Examples of film-forming biopolymers include © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ECF24 organizers а Medical University “Prof. Dr. Paraskev Stoyanov”, Faculty of Pharmacy, Varna, Bulgaria b University of Plovdiv “Paisii Hilendarski”, Faculty of Physics and Technology, Plovdiv, Bulgaria c Medical University—Pleven, Faculty of Pharmacy, 5800 Pleven, Bulgaria а Medical University “Prof. Dr. Paraskev Stoyanov”, Faculty of Pharmacy, Varna, Bulgaria b University of Plovdiv “Paisii Hilendarski”, Faculty of Physics and Technology, Plovdiv, Bulgaria c Medical University—Pleven, Faculty of Pharmacy, 5800 Pleven, Bulgaria Abstract Polysaccharide films with essential oil of tea tree ( Melaleuca alternifolia ) with a concentration of 1% were developed by casting and evaporation of the solvent. To improve the mechanical properties of the films, plasticizer glycerol was added. The intermolecular interactions of polysaccharides and essential oil were evaluated, and for this purpose, the infrared spectra were taken using Fourier transformation. Film surface was examined using an electron scanning microscope. Data were obtained on the mechanical properties of the films, such as deformation, strength, and modulus of elasticity. The research results confirm the potential for incorporating essential oils into the polysaccharide matrix for food applications as edible films. © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ECF24 organizers Keywords: chitosan, pectin, HPMC, alginate, edible films, tea tree oil 1. Introduction Edible biopolymers and food-grade ingredients are commonly utilized to create edible films and coatings. Edible films are defined as thin layers of consumable material applied as a protective covering on food items, and they can be eaten along with the product itself (Galus et al., 2020). Examples of film-forming biopolymers include

* Corresponding author. Tel.:+359- 897-832-793; E-mail address: Krastena.Nikolova@mu-varna.bg * Corresponding author. Tel.:+359- 897-832-793; E-mail address: Krastena.Nikolova@mu-varna.bg

2452-3216 © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ECF24 organizers 2452-3216 © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ECF24 organizers

2452-3216 © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of ECF24 organizers 10.1016/j.prostr.2025.06.140