Natural mucilage edible coatings to reduce post-harvest fruit and vegetable spoilage

Overview

Post-harvest losses of fruits and vegetables remain a major challenge for growers, distributors, and retailers, particularly in regions where cold-chain infrastructure is limited. This solution offers an edible coating technology derived from natural plant mucilage that forms a protective film around fresh produce. The coating modifies the internal atmosphere of the fruit, acts as a barrier against oxygen, carbon dioxide, water vapour, and aroma compounds, and slows respiration rates, thereby delaying deterioration and microbial spoilage.

The technology uses mucilage isolated from two plant sources, Ceratotheca sesamoides and Shorea robusta, both processed through a straightforward dry extraction method. Coatings are applied by dipping fresh produce in the coating solution at room temperature for one minute, followed by uniform rotation and air drying. Because the materials are edible and plant-based, the approach is environmentally friendly and avoids the regulatory and consumer concerns associated with synthetic waxes and chemical treatments.

Technical specifications

Coating materials:

• Mucilage extracted from Ceratotheca sesamoides (CS)
• Mucilage extracted from Shorea robusta (SR)

Application process:

• Fresh produce is dipped in the coating solution at room temperature for approximately one minute
• Samples are rotated to ensure uniform coverage
• Coated produce is dried and stored at room temperature

Observed performance on tomato fruits:

• SR coating maintained the lowest weight loss, reaching 17.91% at 32 days compared with 19.39% for uncoated samples
• Uncoated tomatoes showed spoilage by day 24, while coated samples remained market-acceptable through day 32
• Nutrient composition of coated tomatoes was preserved
• Statistical analysis showed significant differences (P<0.05) between coated and uncoated samples throughout storage

Functional benefits of the edible film:

• Barrier to oxygen, carbon dioxide, water vapour, and aroma compounds
• Reduced respiration rate of the produce
• Protection against microbial spoilage

Technology readiness level

The coating formulations have been validated in controlled laboratory experiments on tomato fruits, with statistically significant shelf-life extension demonstrated over a 32-day storage period. The Shorea robusta formulation showed the strongest performance and is the lead candidate for further development. The team plans to extend testing to additional edible coatings and a broader range of fruits and vegetables. Commercial-scale pilot trials, optimisation of coating formulations for different produce types, and regulatory review for food-contact use represent the next steps toward market readiness.