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0INTERNATIONAL SCIENTIFIC AND PRACTICAL CONFERENCE "STATUS AND DEVELOPMENT PROSPECTS OF FUNDAMENTAL AND APPLIED MICROBIOLOGY: THE VIEWPOINT OF YOUNG SCIENTISTS" _25-26 SEPTEMBER, 2024_
EDIBLE COATINGS: A SUSTAINABLE APPROACH TO PROLONGING FRESH PRODUCE SHELF LIFE
1Swati Sharma, 2Smita Rai, 3Shefali Singh
1Assistant Professor, Department of Biosciences, Integral University, Lucknow 2Research Scholar, Department of Biosciences, Integral University, Lucknow 3Research Scholar, Department of Biosciences, Integral University, Lucknow https://doi.org/10.5281/zenodo.13847141
Abstract. Global food security and the sustainable production of enough high-quality, highly nutritious food is made more difficult by the world's population growth. Vegetables and fruits have a significant role in a balanced diet and the prevention of malnutrition in humans. The postharvest quality loss is caused by certain changes. The main factors causing harvested fruit and vegetables lose quality include a high water content and continues to metabolize after harvesting, which causes ripening, increased susceptibility to fungus that cause deterioration, and reactive oxygen species, enhanced microbial development and activity of enzymes that break down cell walls, and an even higher rate of respiration. These factors also cause textural alterations, weight loss, physiological problems, and decay. Reducing these losses can make them more readily available and enable transportation to remote areas. Fruit and vegetable quality is preserved and shelf life is extended by postharvest methods including heat and chemical treatments. Edible coatings can help reduce waste, respect the environment, and improve consumer health because they are made from naturally existing renewable resources. Chitosan and other edible coatings form a thin layer surrounding fresh produce that acts as a protective agent, extending shelf life, and have the potential to control their ripening process and maintain nutritional properties of the coated product. This review discusses recent research on the application of chitosan and other edible coatings to prevent fungal decay, keep the quality, and reduce fresh product waste.
Edible Coatings to Improve the Post-Harvest Quality of Food
The purpose of edible coatings is to create a barrier against moisture, oxygen, and solute movement for food by applying thin layers of edible material to the product surface either in place of or in addition to naturally occurring protective waxy coatings [1]. To generate a changed environment, they are immediately applied to the food surface by dipping, spraying, or brushing [2]. The materials used to prepare edible films and coatings should be FDA-approved generally recognized as safe (GRAS) materials because they will be ingested, and they also need to meet all applicable standards for the specific food product [3]. A coating that prolongs the shelf life of fresh produce without promoting anaerobiosis and lessens deterioration without compromising quality is considered optimal [4]. Although fresh food has historically been the target application for edible coatings, their potential has recently expanded due to the advent of designed edible coatings with a wider variety of permeability properties [5]. Fruit-based coatings provide enhanced nutrition to products, which increases their market value. Edible and biodegradable coatings must meet a number of special functional requirements, for example, moisture barrier, solute or gas barrier, water/lipid solubility, color and appearance, mechanical characteristics, nontoxicity, etc [6]. The effect of coatings on fruits and vegetables depends greatly on temperature, alkalinity, thickness and type of coating, and the variety and condition of fruit and vegetable [7].
INTERNATIONAL SCIENTIFIC AND PRACTICAL CONFERENCE "STATUS AND DEVELOPMENT PROSPECTS OF FUNDAMENTAL AND APPLIED MICROBIOLOGY: THE VIEWPOINT OF YOUNG SCIENTISTS" _25-26 SEPTEMBER, 2024_
Edible coatings represent a promising innovation in food science, especially for prolonging the shelf life of fresh produce. By applying a thin, consumable layer to fruits and vegetables, these coatings serve as a protective barrier, reducing moisture loss, regulating gas exchange, and preventing microbial contamination [8].
A variety of natural substances, such as polysaccharides (like starch and alginates), proteins (like casein and gelatin) [9], and lipids (like beeswax and fats), can be used to create edible coatings [10]. The various qualities of each substance can impact the coating's efficacy. These coatings can help retain moisture, slow down ripening, and reduce spoilage by minimizing exposure to oxygen and contaminants. They can also enhance the appearance of produce, making it look fresher. Edible coatings contribute to sustainability by reducing food waste and extending the shelf life of products, which can lead to fewer resources used for food production and distribution. Additionally, many coatings are made from biodegradable materials, further reducing environmental impact [11].
Composition of Edible Coatings
Materials that have the potential to form films can be used to create edible coatings. Film materials need to be dissolved and distributed in a solvent throughout the production process. This solvent might be water, alcohol, a combination of water and alcohol, or a combination of other solvents [5]. Plasticizers, antimicrobial agents, minerals, vitamins, colors, or flavors can be added in this process. Adjusting the pH and/or heating the solutions may be done for the specific polymer to facilitate dispersion [11]. Films, the film solution is then cast and dried at the appropriate temperature and relative humidity. There are several ways to apply the film solutions on food, including dipping, spraying, brushing, and panning, followed by drying. Composites, proteins, lipids, and polysaccharides can all be found in edible coatings [13]. Their presence and abundance determine the barrier properties of material with regard to water vapor, oxygen, carbon dioxide, and lipid trans- fer in food systems [7].
Properties of Edible Coatings
The properties of edible coating depend primarily on molecular structure rather than molecular size and chemical constitution. Specific requirements for edible films and coatings are .The coating should be water-resistant so that it remains intact and covers a product adequately, when applied [12].
It should not deplete oxygen or build up excessive carbon dioxide. A minimum of 1-3% oxygen is required around a commodity to avoid a shift from aerobic to anaerobic respiration.
It should reduce water vapor permeability.
It should improve appearance, maintain structural integrity, improve mechanical handling properties, carry active agents (antioxidants, vitamins, etc.) and retain volatile flavor compounds. It should melt above 40°C without decomposition.
It should be easily emulsifiable, non-sticky or should not be tacky, and have efficient drying performance.
It should never interfere with the quality of fresh fruit or vegetable and not impart undesirable order.
It should have low viscosity and be economical.
It should be translucent to opaque but not like glass and capable to tolerate slight pressure.
Application of Edible Coatings
INTERNATIONAL SCIENTIFIC AND PRACTICAL CONFERENCE "STATUS AND DEVELOPMENT PROSPECTS OF FUNDAMENTAL AND APPLIED MICROBIOLOGY: THE VIEWPOINT OF YOUNG SCIENTISTS" 25-26 SEPTEMBER, 2024
Edible coatings have a wide range of applications in food preservation, especially for fresh produce, and can be tailored to the specific needs of different products. They are commonly used for fruits, vegetables, and even some perishable products like cheese [14]. The choice of coating material and method often depends on the specific type of produce and desired shelf life extension. Coatings slow down the respiration rate by limiting oxygen exposure, reducing ethylene production (which speeds up ripening), and thereby extending shelf life. Antimicrobial agents can be incorporated into coatings to prevent mold, yeast, and bacterial growth on the surface of fresh produce [3].
Conclusion
Edible coatings have broad applications across many food categories, providing benefits like extended shelf life, moisture retention, and microbial protection while maintaining the food's sensory quality and safety. Edible coatings represent a promising and sustainable technology for improving food preservation and reducing waste.
REFERENCES
1. Sason, G. and Nussinovitch, A., 2021. Hydrocolloids for edible films, coatings, and food packaging. In Handbook of Hydrocolloids (pp. 195-235). Woodhead Publishing.
2. Ghasemlou, M., Oladzadabbasabadi, N., Ivanova, E.P., Adhikari, B. and Barrow, C.J., 2024. Engineered Sustainable Omniphobic Coatings to Control Liquid Spreading on Food-Contact Materials. ACS Applied Materials & Interfaces, 16(13), pp.15657-15686.
3. Anis, A., Pal, K. and Al-Zahrani, S.M., 2021. Essential oil-containing polysaccharide-based edible films and coatings for food security applications. Polymers, 13(4), p.575.
4. Qu, P., Zhang, M., Fan, K., & Guo, Z. 2022. Microporous modified atmosphere packaging to extend shelf life of fresh foods: A review. Critical Reviews in Food Science and Nutrition, 62(1), 51-65.
5. Ribeiro, A. M., Estevinho, B. N., & Rocha, F., 2021. Preparation and incorporation of functional ingredients in edible films and coatings. Food andBioprocess Technology, 14, 209231.
6. Erginkaya, Z., Kalkan, S. and Unal, E., 2014. Use of antimicrobial edible films and coatings as packaging materials for food safety. In Food processing: Strategies for quality assessment (pp. 261-295). New York, NY: Springer New York.
7. Dhall, R.K., 2013. Advances in edible coatings for fresh fruits and vegetables: a review. Critical reviews in food science and nutrition, 53(5), pp.435-450.
8. Chettri, S., Sharma, N. and Mohite, A.M., 2023. Edible coatings and films for shelf-life extension of fruit and vegetables. Biomaterials advances, p.213632.
9. Mohamed, S.A., El-Sakhawy, M. and El-Sakhawy, M.A.M., 2020. Polysaccharides, protein and lipid-based natural edible films in food packaging: A review. Carbohydrate polymers, 238, p.116178.
10. Moghtadaei, M., Soltanizadeh, N. and Goli, S.A.H., 2018. Production of sesame oil oleogels based on beeswax and application as partial substitutes of animal fat in beef burger. Food Research International, 108, pp.368-377.
11. Khalid, S., Naeem, M., Talha, M., Hassan, S. A., Ali, A., Maan, A. A., ... & Aadil, R. M. (2024). Development of biodegradable coatings by the incorporation of essential oils derived
INTERNATIONAL SCIENTIFIC AND PRACTICAL CONFERENCE "STATUS AND DEVELOPMENT PROSPECTS OF FUNDAMENTAL AND APPLIED MICROBIOLOGY: THE VIEWPOINT OF YOUNG SCIENTISTS" _25-26 SEPTEMBER, 2024_
from food waste: A new sustainable packaging approach. Packaging Technology and Science, 37(3), 167-185.
12. Lin, H., Kehinde, O., Lin, C., Fei, M., Li, R., Zhang, X., Yang, W. and Li, J., 2024. Mechanically strong micro-nano fibrillated cellulose paper with improved barrier and water-resistant properties for replacing plastic. International Journal of Biological Macromolecules, 263, p.130102.
13. Xiao, Q., 2021. Coating and film-forming properties. Foodhydrocolloids: Functionalities and applications, pp.267-306.
14. Arnon-Rips, H. and Poverenov, E., 2018. Improving food products' quality and storability by using Layer by Layer edible coatings. Trends in Food Science & Technology, 75, pp.81-92.
