ITMO scientists are developing a colorimetric indicator that changes color when ready meals spoil, right on the packaging.
Scientists at ITMO University are creating a new format of 'smart' packaging that could visually show the actual state of ready meals directly on the package. The laboratory prototype was presented by Yaroslav Ionov, a graduate student at the Center for Molecular and Biological Technologies of ITMO, at the young researchers' conference in the 'Biotechnology' section of the XIII Russian Biotech Forum OpenBio.
The development is aimed primarily at ready-to-eat dishes, a segment whose demand in Russia is steadily growing. The principle of the 'smart' packaging is based on a colorimetric indicator: when volatile compounds associated with food spoilage appear, the label changes color.
Unlike the previous version presented in 2024, the new indicator does not require special equipment from the buyer. Previously, reading the data required UV lighting, a smartphone camera, and software image processing. Now the product state can be assessed simply by the color change of the label on the container.
Key features of the new technology:
- Label color changes upon contact with spoilage compounds (strongest reaction to hydrogen sulfide);
- Agar-based indicator films retain properties after lamination at temperatures up to 100 °C;
- Application of the label by flexographic printing directly on the packaging is being considered;
- Freshness assessment is available visually, without additional devices.
First tests on individual salad components showed the developed variant performs better with protein products than with plant components, so the team began an additional development cycle. In particular, researchers are testing the indicator with a plant active substance — anthocyanin from hibiscus.
The project is developing with financial support from the Russian Science Foundation (RSF). In 2024, RSF allocated 6 million rubles (3 million rubles each in 2025 and 2026) — then ITMO scientists first proposed using carbon-dot-based fluorescent indicators to determine the actual shelf life of meat, fish, and poultry.
In the second stage, specialists created optical test systems and biosensors based on carbon dots, as well as a portable smartphone-compatible device for signal registration outside laboratory conditions. The sensor system was successfully tested on real food samples: researchers determined the hydrogen peroxide content in milk and glucose in apple juice, with results matching reference analysis methods.
Separately, the project authors assessed the safety of the new materials. Tests showed that carbon dots and hybrid materials based on them meet the requirements of the standard for materials in contact with food. Using nanocrystalline chitosan as a carrier reduced nanoparticle migration from the packaging from 39.5% to 4.5%. One material also showed pronounced antimicrobial activity.
Following the second stage, the researchers stated that the developed biosensor systems could become the basis for creating new 'intelligent' food packaging materials that allow quick product quality control and reduce the risk of selling spoiled products.
Source: Sibmeda
