Food waste is a major problem for developed countries, as millions of tons of food products are disposed of because they are not eaten before their "best before" date has expired. An international team of researchers may have come up with a new solution that has the potential to dramatically reduce food waste.
Researchers at the Dutch Eindhoven University of Technology, Universita di Catania in Italy, CEA-Liten in France and STMicroelectronics, one of the world's largest semiconductor companies, have invented a plastic analog-digital converter that can be used in packaging to measure food freshness. The invention was presented at the International Solid-State Circuits Conference in San Francisco.
The plastic sensor circuits, costing less than 1 euro cent each, could help solve the food waste problem and can be used for a number of different purposes, including in pharmaceuticals. These sensors could be included in the package of the product to monitor its acidity level, for instance. Data that the sensor circuit detects could be read with a scanner or with a mobile phone to show consumers the freshness of meat or even if frozen food had been defrosted earlier. The sensor circuit consists of four components — the sensor, an amplifier, an analog-digital converter to digitize the signal and a radio transmitter that can send the data to a digital device such as a mobile phone or a scanner.
Researchers explained that food waste can largely be attributed to the fact that it is difficult to assess how long a product can stay usable. "Best before" dates are usually defined as estimates but having a sensor that can determine the state of the food inside the package could significantly reduce the amount of food being dumped because of its expiry date.
It is estimated that in developed countries the total food waste equals 100 kg per person per year, according to a 2011 study from the Food and Agriculture Organization of the United Nations. This is not only a financial burden for customers themselves but is also detrimental to the environment and natural resources, Eindhoven University of Technology said in a statement. Researcher Eugenio Cantatore of Eindhoven University of Technology commented that actually such sensors are already in use, such as those based on standard silicon ICs (integrated chips). However, those are too expensive, with an estimated cost of ten cents per piece, which is "too much for a 1-euro bag of crisps," he added.
Cantatore explained that the team of researchers was now working on developing electronic devices that were made entirely from plastic rather than silicon because they will not only be cheaper to produce but will also be suitable to be included in plastic packaging. The plastic semiconductor could even be printed on various types of flexible surfaces, which would make it much cheaper to use. He estimated that the whole process until the device could reach supermarket shelves would take at least five years.