Dual-Action Preservation: Scientists Combine Cold Plasma and "Smart" Nano-Coatings to Extend Tomato Shelf Life and Neutralize Pesticides

Jiangsu researchers combine DBD plasma with a gold-nanoparticle coating to extend tomato shelf life and double pesticide removal efficiency.

By: AXL Media

Published: Apr 3, 2026, 10:49 AM EDT

Source: Information for this report was sourced from Food Materials Research

Addressing the Vulnerability of Fresh Produce

Cherry tomatoes are a high-value crop, yet their thin skins and high moisture content make them notoriously difficult to store. Postharvest deterioration is typically driven by microbial spoilage, rapid moisture loss, and the presence of agricultural chemicals like chlorpyrifos. While individual treatments such as edible coatings or cold plasma have shown promise, they often lack the penetration depth or stability to provide a complete solution. A new study published in Food Materials Research identifies a combined strategy that acts as both a physical barrier and a chemical purifier, offering a sustainable alternative to traditional chemical preservatives.

The Science of "Smart" Edible Coatings

The research team, led by Jie Zou, synthesized a sophisticated composite film using sodium alginate (SA) as a base matrix. To give the film "smart" properties, they incorporated DAT nanoparticles—titanium dioxide modified with gold nanoparticles and D-cysteine. These nanoparticles were specifically engineered for their mechanical strength and barrier performance. When tomatoes are dipped in this solution, they receive a protective layer that significantly reduces weight loss and maintains fruit firmness. Experimental results showed that after 11 days of storage, treated tomatoes remained 1.36 times firmer than those without the coating.

Synergy with Cold Plasma Technology

The breakthrough of this system lies in the interaction between the coating and Dielectric Barrier Discharge (DBD) plasma. After the coating is applied, the fruit is exposed to a 140 kV plasma field for three minutes. This process does more than just kill surface bacteria; the UV radiation generated by the plasma reacts with the photocatalytic DAT nanoparticles in the coating. This interaction produces reactive oxygen species (ROS) that actively break down complex pesticide molecules. While natural degradation only removed about 31% of chlorpyrifos residues, this integrated system achieved a 65.86% degradation rate, bringing residue levels well below regulatory safety limits.