Physical and Microbiological Evaluation of Chitosan Films: Effect of Essential Oils and Storage
The effect of the inclusion of thyme and rosemary essential oils into chitosan films, as well as the microbiological and physical properties when storing chitosan film with and without the mentioned inclusion was studied. The film forming solution was prepared by dissolving chitosan (2%, w/v), polysorbate 80 (4% w/w CH) and glycerol (16% w/w CH) in aqueous lactic acid solutions (control). The thyme (TEO) and rosemary (REO) essential oils (EOs) were included 1:1 w/w (EOs:CH) on their combination 50/50 (TEO:REO). The films were stored at temperatures of 5, 20, 33°C and a relative humidity of 75% during four weeks. The films with essential oil inclusion did not show an antimicrobial activity against strains. This behavior could be explained because the chitosan only inhibits the growth of microorganisms in direct contact with the active sites. However, the inhibition capacity of TEO was higher than the REO and a synergic effect between TEO:REO was found for S. enteritidis strains in the chitosan solution. Some physical properties were modified by the inclusion of essential oils. The addition of essential oils does not affect the mechanical properties (tensile strength, elongation at break, puncture deformation), the water solubility, the swelling index nor the DSC behavior. However, the essential oil inclusion can significantly decrease the thickness, the moisture content, and the L* value of films whereas the b* value increased due to molecular interactions between the polymeric matrix, the loosing of the structure, and the chemical modifications. On the other hand, the temperature and time of storage changed some physical properties on the chitosan films. This could have occurred because of chemical changes, such as swelling in the presence of high humidity air and the reacetylation of amino groups. In the majority of cases, properties such as moisture content, tensile strength, elongation at break, puncture deformation, a*, b*, chrome, 7E increased whereas water resistance, swelling index, L*, and hue angle decreased.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1099038Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2562
 M. Rinaudo, "Main properties and current applications of some polysaccharides as biomaterials," Polymer International, vol. 57, Mar 2008, pp. 397-430.
 R. N. Tharanathan and F. S. Kittur, "Chitin - The undisputed biomolecule of great potential," Critical Reviews in Food Science and Nutrition, vol. 43, 2003, pp. 61-87.
 M. N. V. Ravi Kumar, "A review of chitin and chitosan applications," Reactive and Functional Polymers, vol. 46, 2000, pp. 1-27.
 J. Dutta, et al., "Progress in antimicrobial activities of chitin, chitosan and its oligosaccharides: a systematic study needs for food applications," Food Science and Technology International, vol. 18, Feb 2012, pp. 3-34.
 E. R. Kenawy, et al., "The chemistry and applications of antimicrobial polymers: A state-of-the-art review," Biomacromolecules, vol. 8, 2007, pp. 1359-1384.
 M. Kong, et al., "Antimicrobial properties of chitosan and mode of action: A state of the art review," International Journal of Food Microbiology, vol. 144, 2010, pp. 51-63.
 E. I. Rabea, et al., "Chitosan as antimicrobial agent: applications and mode of action," Biomacromolecules, vol. 4, 2003, pp. 1457-1465.
 K. S. Miller and J. M. Krochta, "Oxygen and aroma barrier properties of edible films: A review," Trends in Food Science and Technology, vol. 8, 1997, pp. 228-237.
 A. G. Cunha and A. Gandini, "Turning polysaccharides into hydrophobic materials: a critical review. Part 2. Hemicelluloses, chitin/chitosan, starch, pectin and alginates," Cellulose, vol. 17, Dec 2010, pp. 1045-1065.
 Z. Abdeen, "Swelling and reswelling characteristics of cross-linked poly(vinyl alcohol)/chitosan hydrogel film," Journal of Dispersion Science and Technology, vol. 32, 2011, pp. 1337-1344.
 M. Moradi, et al., "Characterization of antioxidant chitosan film incorporated with Zataria multiflora Boiss essential oil and grape seed extract," Lwt-Food Science and Technology, vol. 46, May 2012, pp. 477-484.
 D. Altiok, et al., "Physical, antibacterial and antioxidant properties of chitosan films incorporated with thyme oil for potential wound healing applications," Journal of Materials Science-Materials in Medicine, vol. 21, Jul 2010, pp. 2227-2236.
 Y. Pranoto, et al., "Enhancing antimicrobial activity of chitosan films by incorporating garlic oil, potassium sorbate and nisin," Lwt-Food Science and Technology, vol. 38, 2005, pp. 859-865.
 R. M. Raybaudi-Massilia, et al., "Control of pathogenic and spoilage microorganisms in fresh-cut fruits and fruit juices by traditional and alternative natural antimicrobials," Comprehensive Reviews in Food Science and Food Safety, vol. 8, Jul 2009, pp. 157-180.
 R. Avila-Sosa, et al., "Antifungal activity by vapor contact of essential oils added to amaranth, chitosan, or starch edible films," International Journal of Food Microbiology, vol. 153, Feb 2012, pp. 66-72.
 J. Gomez-Estaca, et al., "antimicrobial activity of composite edible films based on fish gelatin and chitosan incorporated with clove essential oil," Journal of Aquatic Food Product Technology, vol. 18, Jun 2009, pp. 46-52.
 L. Hernandez-Ochoa, et al., "Study of the antibacterial activity of chitosan-based films prepared with different molecular weights including spices essential oils and functional extracts as antimicrobial agents," Revista Mexicana De Ingenieria Quimica, vol. 10, Dec 2011, pp. 455-463.
 L. Sanchez-Gonzalez, et al., "Physical and antimicrobial properties of chitosan-tea tree essential oil composite films," Journal of Food Engineering, vol. 98, Jun 2010, pp. 443-452.
 L. Sanchez-Gonzalez, et al., "Antimicrobial activity of polysaccharide films containing essential oils," Food Control, vol. 22, Aug 2011, pp. 1302-1310.
 Y. Zhong and Y. F. Li, "Effects of storage conditions and acid solvent types on structural, mechanical and physical properties of kudzu starch (Pueraria lobata)- Chitosan composite films," Starch-Starke, vol. 63, Sep 2011, pp. 579-586.
 C. Caner, et al., "Chitosan film mechanical and permeation properties as affected by acid, plasticizer, and storage," Journal of Food Science, vol. 63, 1998, pp. 1049-1053.
 G. Kerch and V. Korkhov, "Effect of storage time and temperature on structure, mechanical and barrier properties of chitosan-based films," European Food Research and Technology, vol. 232, Jan 2011, pp. 17-22.
 N. E. Suyatma, et al., "Effects of hydrophilic plasticizers on mechanical, thermal, and surface properties of chitosan films," Journal of Agricultural and Food Chemistry, vol. 53, May 2005, pp. 3950-3957.
 L. Nud'ga, et al., "Chemical and structural transformations in chitosan films in the course of storage," Russian Journal of Applied Chemistry, vol. 81, Nov 2008, pp. 1992-1996.
 Y. Deng, et al., "Changes in physical properties of chitosan films at subzero temperatures," Ital. J. Food Sci.., vol. 21, 2009, pp. 487-497.
 P. C. Srinivasa and R. N. Tharanathan, "Chitin/chitosan - Safe, ecofriendly packaging materials with multiple potential uses," Food Reviews International, vol. 23, Mar 2007, pp. 53-72,.
 B. L. Butler, et al., "Mechanical and barrier properties of edible chitosan films as affected by composition and storage," Journal of Food Science, vol. 61, 1996, pp. 953-956.
 P. Fernandez-Saiz, et al., "Optimization of the film-forming and storage conditions of chitosan as an antimicrobial agent," Journal of Agricultural and Food Chemistry, vol. 57, Apr 2009, pp. 3298-3307.
 P. Hernández-Muñoz, et al., "mechanical and water barrier properties of glutenin films influenced by storage time," Journal of Agricultural and Food Chemistry, vol. 52, 2004, pp. 79-83.
 M. H. Hosseini, et al., "Antimicrobial, physical and mechanical properties of chitosan-based films incorporated with thyme, clove and cinnamon essential oils," Journal of Food Processing and Preservation, vol. 33, Dec 2009, pp. 727-743.
 S. M. Ojagh, et al., "Development and evaluation of a novel biodegradable film made from chitosan and cinnamon essential oil with low affinity toward water," Food Chemistry, vol. 122, 2010, pp. 161-166.
 W. L. Cao, et al., "Physical, mechanical and degradation properties, and Schwann cell affinity of cross-linked chitosan films," Journal of Biomaterials Science-Polymer Edition, vol. 16, 2005, pp. 791-807.
 I. A. Sogias, et al., "Exploring the factors affecting the solubility of chitosan in water," Macromolecular Chemistry and Physics, vol. 211, Feb 2010, pp. 426-433.
 V. Coma, et al., "Edible antimicrobial films based on chitosan matrix," Journal of Food Science, vol. 67, 2002, pp. 1162-1169.
 J. Gutierrez, et al., "The antimicrobial efficacy of plant essential oil combinations and interactions with food ingredients," International Journal of Food Microbiology, vol. 124, 2008, pp. 91-97.
 L. E. Abugoch, et al., "Characterization of quinoa protein-chitosan blend edible films," Food Hydrocolloids, vol. 25, Jul 2011, pp. 879-886.
 L. Sanchez-Gonzalez, et al., "Physical properties of edible chitosan films containing bergamot essential oil and their inhibitory action on Penicillium italicum," Carbohydrate Polymers, vol. 82, Sep 2010, pp. 277-283.
 C. A. Murray and J. R. Dutcher, "Effect of changes in relative humidity and temperature on ultrathin chitosan films," Biomacromolecules, vol. 7, Dec 2006, pp. 3460-3465.
 M. Abdollahi, et al., "A novel active bionanocomposite film incorporating rosemary essential oil and nanoclay into chitosan," Journal of Food Engineering, vol. 111, Jul 2012, pp. 343-350.
 P. C. Srinivasa, et al., "Effect of plasticizers and fatty acids on mechanical and permeability characteristics of chitosan films," Food Hydrocolloids, vol. 21, Oct 2007, pp. 1113-1122.
 J. L. Wiles, et al., "Water vapor transmission rates and sorption behavior of chitosan films," Journal of Food Science, vol. 65, 2000, pp. 1175-1179.
 W. X. Du, et al., "Effects of allspice, cinnamon, and clove bud essential oils in edible apple films on physical properties and antimicrobial activities," Journal of Food Science, vol. 74, 2009, pp. M372-M378.
 L. Sánchez-González, et al., "Characterization of edible films based on hydroxypropylmethylcellulose and tea tree essential oil," Food Hydrocolloids, vol. 23, 2009, pp. 2102-2109.
 J. Duan, et al., "Storability of antimicrobial chitosan-lysozyme composite coating and film-forming solutions," Journal of Food Science, vol. 73, Aug 2008, pp. M321-M329.
 B. Cuq, et al., "Stability of myofibrillar protein-based biopackagings during storage," LWT - Food Science and Technology, vol. 29, 1996, pp. 344-348.
 M. Abdollahi, et al., "Improvement of active chitosan film properties with rosemary essential oil for food packaging," International Journal of Food Science and Technology, vol. 47, Apr 2012, pp. 847-853.
 E. M. A. El-Hefian, et al., "Preparation and characterization of chitosan/agar blends: rheological and thermal studies," Journal of the Chilean Chemical Society, vol. 55, Mar 2010, pp. 130-136.
 M. F. Cervera, et al., "Solid-state characterization of chitosans derived from lobster chitin," Carbohydrate Polymers, vol. 58, 2004, pp. 401-408.