Detection of spoiled food along the supply chain with novel sensors for packed food

Along food supply chains, several critical steps can lead to inconsumable food. Especially food of animal origin undergoes rapid aging, when stored inadequately. Quality assessment of packaged food products faces serious problems ranging from the loss of integrity of the package to damage of the food and it is applied only to a low number of samples per batch. As a result, food products are either wasted or not analyzed, which results in a significant decrease in food safety. As a part of an intelligent packaging system, we designed a sensor foil that can detect amines, produced during the food aging process. Change of the fluorescence of the sensor foil can be assessed with spectroscopy or color change from green to red can be detected optically with a camera, e.g. by smartphone. The foil can be incorporated inside the single packaging units and noninvasively measured routinely by the store or consumer. The readout of the foils was performed with steady-state tabletop spectrometers, which were then compared to the results for readouts with different inexpensive handheld devices that could be used during real-life applications, e.g., at any step in a food supply chain. Ideally, the single food product is linked to a single foil at the primary producer, measuring the first spectrum and connecting the data to the specific product, e.g. via distributed ledger. For a transparent process chain, QR-codes could be utilized to allow access to the freshness data along the shelf life of a single package.