The spontaneous barbecue party has been decided, and you’ve quickly bought sausages and ready-made salads from the supermarket. What will keep for how long? And what does the best-before date on the packaging actually mean? These questions concern consumers, but also retailers. After all, freshness and hygiene are the be-all and end-all. On top of that, too much food is thrown away due to premature spoilage.
Against this backdrop, the dissertation on intelligent packaging by Claudia Waldhans from Bonn, which was awarded the Wissenschaftspreis 2025, is of particular importance. The EHI Retail Institute e.V. and GS1 Science Award is supported by Arvato Systems, Epam, Devoteam, Ferrero, and KPMG.
Avoiding Food Waste
Claudia Waldhans has developed an app and server-based database that can monitor the temperature and shelf life of packaged fresh produce along selected supply chains. The development took place in collaboration with several research partners as part of a research project.
The app is able to provide a detailed color reading. Both in the laboratory and in practical studies, it has been shown that the app can be used to predict the remaining shelf life of the analyzed products under various simulated temperature conditions.
This is how it works: A special label is attached to the packaging, the color changes of which indicate temperature differences. It is attached to the packaging and reacts to the ambient temperature. Possible food spoilage becomes visible through a change in color. The discoloration of the label can also be linked to shelf life models – if it is attached as close as possible to the food, for example to the sausage. However, the label can also be used purely for temperature control, in which case it can also be attached to the crate. Provided that a monitored cold chain is in place.
Intelligent packaging solutions have been the subject of research and development in the food sector for some time now. The Cold Chain Management working group at the University of Bonn has already dealt with this topic in several research projects. But what is completely new about the topic of Waldhan’s work, which was supervised by Professor Judith Kreyenschmidt, is the approach of using a smartphone as an easy-to-use measuring device for reading the labels, which provides objective measured values and can be used to determine the remaining shelf life. In particular, this could reduce the barriers to implementing these systems in practice. This approach was pursued in the “Intelli-Pack” research project, as part of which Claudia Waldhans wrote her dissertation. “After all, everyone has a smartphone,” says Waldhans. In principle, the app developed is, therefore, suitable for all players along the food supply chain, from the producer to the end consumer.
The focus here is on various functions: logisticians and retail employees can determine whether the cold chain has been maintained and what the product’s remaining shelf life is, and can control routes and sales based on the actual time left. For the end customer in particular, the app in conjunction with the label is a good tool for monitoring the temperature and shelf life, which is otherwise not directly possible. This provides valuable additional information about the condition of the product and whether/how long the food is still fit for consumption. “All with the aim of reducing food waste at these stages of the chain.” Even trained staff cannot always recognize the shelf life and edibility of meat or salad with the naked eye, explains Waldhans. “Stored in the heat for 30 minutes too long can cause microbiological damage, so the system is also a suitable tool for monitoring transport.”
The OnVu-TTI label was developed by the universities of Bayreuth and Bonn and the Technicon in Haifa. The companies Freshpoint (today: Evigence Sensors) and Ciba Specialty Chemicals (now part of BASF) took over the further development. Ciba developed the specific color. The label is marketed by BIZERBA Labels & Consumables GmbH, which was also a partner in the Intelli-Pack project. The app is not yet ready for the market.
Claudia Waldhans now works as a project funding officer at the Federal Office for Agriculture and Food in the Digitalization and AI department. However, the topics of food safety and packaging also play a role in her everyday life as a consumer. The next time she goes shopping for a barbecue, at the latest.
By Anna Ntemiris, Editor
