What is the main purpose of the edible coatings?

The edible coatings are designed to protect fruits from post-harvest degradation by reducing water loss, preventing gas exchange, and extending shelf life, ultimately reducing food waste.

What is Chitosan (CS), and why is it used in food coating?

Chitosan is a natural polymer derived from the exoskeletons of crustaceans. It's non-toxic, biodegradable, and has excellent film-forming properties, making it an ideal material for food coatings.

How does the addition of Gallic Acid (GA) enhance the properties of Chitosan?

Gallic acid, a plant-derived compound, improves the antimicrobial and antioxidant properties of the chitosan-based coating, offering better protection against bacterial growth and extending the shelf life of food.

How can edible coatings help reduce food waste?

By improving food preservation during transportation and storage, this green technology can significantly reduce food waste, especially in distribution channels, helping achieve the United Nations' goal of halving food waste by 2030.

Innovative Edible Biofilm To Combat Food Waste And Boost Freshness

These Edible Biofilms can combat food waste and boost freshness by preventing water loss and gas exchange, reducing the need for refrigeration or synthetic preservation, while extending shelf life.

South Korea, Dec. 2024: Significant improvements in transportation technology have made fresh food accessibility considerably easier. However, this progress has been accompanied by escalating concerns about food waste during transportation and storage.

The Environmental Impact of Food Waste in Transportation

Globally, around 17% of food at the retail and consumer levels is wasted, resulting in issues like groundwater contamination, hazardous gas emissions, and the spread of infectious pathogens, all contributing to environmental pollution. To develop efficient, cost-effective, and eco-friendly food preservation technologies, researchers worldwide are studying alternatives for the development of packaging materials. Among these, edible coating made of naturally occurring polymers have shown particular promise.

edible-biofilm-to-extending-shelf-life — Scientists from Chungnam National University, Korea show how a chitosan and gallic acid conjugate can be used as an eco-friendly and non-toxic food coating material to extend the shelf life of perishable fruits.

Chitosan: The Natural Polymer Transforming Food Coatings

These protective coatings can protect fruits from post-harvest degradation by preventing water loss and gas exchange, reducing the need for refrigeration or synthetic preservation while extending shelf life.

Chitin, a natural polymer derived from the crustacean endoskeleton, is chemically modified to produce chitosan (CS). CS is non-toxic, biodegradable, and has remarkable film-forming abilities. However, certain limitations, including weak barriers and low antimicrobial properties, hinder its potential as a food coating material.

Enhancing Chitosan with Gallic Acid for Better Food Protection

To address this limitation, a team of scientists, led by Professor Won Ho Park from Chungnam National University, South Korea, incorporated a polyphenolic compound, gallic acid (GA), to produce a CS-GA conjugate. GA is abundantly available in plants and is well known for its excellent antimicrobial and antioxidant properties.

Elaborating further about their study, Prof. Park says, “We wanted to develop a CS-based edible biofilm with enhanced food coating properties, and we were hopeful that the incorporation of GA might help achieve that.” This paper was made available online on September 16, 2024, and will be published in Volume 463, Issue 2 of Food Chemistry, on January 15, 2025.

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A Game Changer for Freshness: How the New Coating Extends Shelf Life

In this study, the team reports the synthesis and characterization of a CS-GA conjugate film. They compared it with CS films to assess GA’s enhancement effects and tested its efficacy on stored mini bananas and cherry tomatoes.

They observed that the developed film exhibited enhanced mechanical strength, protecting against food damage during transportation, and improved antioxidant properties, leading to extended shelf life. It also showed enhanced antibacterial activity against two types of bacteria, confirming its effectiveness against multiple microbial species and superior UV-blocking capabilities to prevent photo discolouration and damage. It also explained the findings of the storage test.

Prof. Park says, “Many consumers are concerned about remaining coating residues on the fruits. The washability of this conjugate makes it appealing to these consumers. Also, we observed a significant reduction in dehydration, discoloration, and mass loss of the stored fruits when the coating was applied. It indicates shelf life extension and freshness retention.”

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The Future of Sustainable Food Storage and Distribution

Going forward, this green technology could significantly reduce food waste and also contribute to the United Nations’ Sustainability Development Goals of halving food waste by 2030. In his concluding thoughts, Prof. Park says, “In the past, the primary strategy for addressing food waste reduction-related issues was to gather and dispose of food scraps. However, our research suggests that by enhancing food preservation capabilities using eco-friendly approaches, we may significantly reduce food waste occurring during the distribution process.”