Investigating the physicochemical and mechanical properties of edible active films based on gelatin containing essential oils of thyme, oregano and sage

Document Type : Complete scientific research article

Authors

1 Assistant Professor, Department of Food Technology, Faculty of Agriculture, Ilam University, Ilam, Iran

2 Bachelor student of food hygiene, Faculty of paraveterinary, Ilam University, Ilam, Iran

Abstract

Background and objectives: To minimize the use of antibiotics, additives, and chemical preservatives , it is possible to incorporate natural antimicrobial substances into packaging. Recent studies focusing on developing and evaluating edible films have highlighted the effectiveness of essential oils like clove, cinnamon, ginger, and basil in protecting against microbial growth, preventing food spoilage (both chemical and microbial), and reducing food waste. Films containing gelatin display impressive mechanical strength, making them suitable for edible film production due to their ability to form a gel-like structure, which is attributed to the presence of certain amino acids like proline and hydroxyproline. Taking into account the plentiful availability and affordability of thyme, oregano, and sage essential oils in our country, as well as the low cost of gelatin, this particular composition of film has yet to be extensively researched and could serve as a model for widespread implementation in the food industry.
Materials and methods: In this study, we investigated the impact of various concentrations of thyme, oregano, and sage essential oils on thr properties of the resulting gelatin-based films. The study examined different concentrations of essential oil ranging from minimum 0% to highest 4% as the independent variable. The dependent variables included a range of physicochemical tests such as solubility, water permeability, thickness, opacity, and color parameters, as well as mechanical tests including elongation to breaking point, tensile strength, and Young's model. The study utilized a mixed experimental design known as simplex lattice and employed Design Expert13 software for experimental design, analysis of variance, diagram creation, and examining the interactions between variables.
Results: In this research, the highest tensile strength (12 MPa), elongation at break point (26%) and Young's modulus (80 MPa) were found in high concentrations of oregano essential oil (4%). Among the treatments, the lowest solubility was in the high concentration of oregano essential oil in the mixture (4% area) and the lowest vapor permeability was in the area of low concentration of oregano essential oil in the mixture. The difference in the amount of turbidity of the resulting films was not significant, although it was the highest in the lowest concentration of oregano essential oil. The highest amount of thickness was obtained in the concentration of oregano essential oil in the region of 4%, which was statistically significant. By increasing the concentration of essential oil thyme in the mixture, the hue angle, whiteness index and saturation decrease, and its highest amount is in the area of 4% oregano and sage. The changes of a* and b* parameters have a trend similar to color indicators, but in relation to L*, the concentration of essential oils has no effect on the changes of this parameter.
Conclusion: The results of this research showed that adding a high concentration of oregano essential oil to the gelatin film compared to thyme and sage essential oils produced films with sufficient strength that have the highest efficiency and desirable characteristics compared to thyme and sage essential oils. It has a flower and can be used as a suitable coating for food protection by delaying the oxidation of lipids, mechanical properties and favorable color changes.

Keywords

Main Subjects


  1. 1.Piermaria, J.A., Pinotti, A., Garcia, M.A., and Abraham, A.G. 2009. Films based on kefiran, an exopolysaccharide obtained from kefir grain: development and characterization. Food Hydrocolloids. 23(3):684-90.

    2.Hanani, Z.N., Roos, Y.H., and Kerry, J. 2014. Use and application of gelatin as potential biodegradable packaging materials for food products. International journal of biological macromolecules. 71:94-102.

    3.Wu, J., Sun, X., Guo, X Ge, S., and Zhang, Q. 2017. Physicochemical properties, antimicrobial activity and oil release of fish gelatin films incorporated with cinnamon essential oil, Aquaculture and Fisheries. 2(4):185-92.

    4.Ejaz, M., Arfat, YA., Mulla, M., Ahmed, J. 2018. Zinc oxide nanorods/clove essential oil incorporated Type B gelatin composite films and its applicability for shrimp packaging. Food Packaging and Shelf Life. 15:113-21.

    5.Gennadios, A.2002. Protein-based films and coatings: CRC Press.

    6.Bonilla, J., Poloni, T., Lourenço, RV., and Sobral, PJ. 2018. Antioxidant potential of eugenol and ginger essential oils with gelatin/chitosan films. Food bioscience. 23:107-14.

    7.Zafarani, M., Ojagh, SM., Alishahi, A., and Kazemi, M. 2017. The effect of chitosan type on the properties of biodegradable films produced from gelatin obtained from the skin of elephant fish. Quarterly journal of new food technologies. 6(1): 149-159.

    8.Martucci, JF., Gende, LB., Neira, L., and Ruseckaite, R.A. 2015. Oregano and lavender essential oils as antioxidant and antimicrobial additives of biogenic gelatin films. Industrial Crops and Products. 71:205-13.

    9.Ghadermarzi, R., Keramat, J. and Goli SA, 2013. The effect of oregano essential oil on the properties of hydroxypropyl methyl cellulose edible film. Quarterly journal of new food technologies. 2(7) 61-74.

    10.Akhter, R., Masoodi, F., Wani, TA., and Rather, SA. 2019. Functional characterization of biopolymer based composite film: Incorporation of natural essential oils and antimicrobial agents. International journal of biological macromolecules. 137:1245-55.

    11.Kavoosi, G., Dadfar, S.M.M. and Purfard, A.M. 2013. Mechanical, physical, antioxidant, and antimicrobial properties of gelatin films incorporated with thymol for potential use as nano wound dressing. Journal of Food Science. 78(2).

    12.Fallah, M., Rouhi, M., Sadeghi, E., Sarlak, Z., Moghadam, A. and Mohammadi, R. 2021. Effects of Olibanum essantial oil on physicochemical, structural, antioxidant and microbial characteristics of Gelatin edible films. Iranian journal of nutrition science and food technology. 15(4): 93-102.

    13.Ejaz, M., Arfat, YA., Mulla, M., and Ahmed, J. 2018. Zinc oxide nanorods/clove essential oil incorporated Type B gelatin composite films and its applicability for shrimp packaging. Food Packaging and Shelf Life. 15:113-21.

    14.Alparslan, Y., Yapıcı, HH., Metin, C., Baygar, T., Günlü, A., and Baygar, T. 2016. Quality assessment of shrimps preserved with orange leaf essential oil incorporated gelatin. LWT-Food Science and Technology. 2016;72:457-66.

    15.Hosseini, M., Rahimi, Z. and saifi, T. 2023. Production of edible film based on gelatin containing thyme essential oil: investigation of its physicochemical, mechanical, antioxidant and microbial properties. Iranian food science and technology. 20(135): 129-139.

    16.Han, JH. 2003. Antimicrobial food packaging. Novel food packaging techniques. 8:50-70.

    17.Langroodi, AM., and Hossein, Tajik. 2017. Antimicrobial effects of hydroalchol sumac extract with chitosan containing zataria multiflora boiss essential oil on beef meat in normal and modified atmosphere packaging. The Journal of Urmia University of Medical Sciences. 28(3):192-205

    18.Piñeros-Hernandez, D., Medina-Jaramillo, C., López-Córdoba, A. and Goyanes, S. 2017. Edible cassava starch films carrying rosemary antioxidant extracts for potential use as active food packaging. Food Hydrocolloids. 63: 488-495.

    1. Tongnuanchan, P., Benjakul, S., Prodpran, T., Pisuchpen, S., and Osako, K. 2016. Mechanical, thermal and heat sealing properties of fish skin gelatin film containing palm oil and basil essential oil with different surfactants. Food Hydrocolloids. 56:93-107.

    20.Pinotti, A., García, M., Martino, M. and Zaritzky, N. 2007. Study on microstructure and physical properties of composite films based on chitosan and methylcellulose. Food Hydrocolloids. 21: 66-2.

    21.Ahmad, M., Benjakul, S., Prodpran, T., and Agustini, TW. 2012. Physico-mechanical and antimicrobial properties of gelatin film from the skin of unicorn leatherjacket incorporated with essential oils. Food Hydrocolloids. 28(1):189-199.

    22.Shojaee-Aliabadi, S., Hosseini, H., Mohammadifar, M A., Mohammadi, A., Ghasemlou, M., Ojagh, SM., Hosseini, S.M. and Khaksar R. 2013. Characterization of antioxidant-antimicrobial κ-carrageenan films containing Satureja hortensis essential oil. International journal of biological macromolecules. 52: 116-124.

    23.Jamróz, E., Juszczak, L., and Kucharek, M. 2018. Investigation of the physical properties, antioxidant and antimicrobial activity of ternary potato starch-furcellaran-gelatin films incorporated with lavender essential oil. International journal of biological macromolecules. 114:1094-101.

    24.Cheng, S., Wang, W., Li, YGao.G., Zhang, K., and Zhou, J. 2019. Cross-linking and film-forming properties of transglutaminase-modified collagen fibers tailored by denaturation temperature. Food chemistry. 271:527-35.

    25.Hosseini, SF., Rezaei, M., Zandi, M. and Farahmandghavi, F. 2015. Bio-based composite edible films containing Origanumvulgare L. essential oil. Industrial Crops and products. 67: 403-413.

    26.Fernández-Cervera, M., Heinämäki, J., Krogars, K., Jörgensern, A. C., Karjalainen, M. and Iraizoz-Colarte, A. 2004. Solid-state and mechanical properties of aqueous chitosan- amylose starch films plasticized with polyols. Journal of Pharmaceutical Science and Technology. 5: 1-6.

    27.Tongnuanchan, P., Benjakul, S., and Prodpran, T. 2012. Properties and antioxidant activity of fish skin gelatin film incorporated with citrus essential oils. Food Chemistry. 134, 1571–1579.