Saving waste: Researchers create heat-tracking technology to identify whether food is still perfectly edible

28 Oct 2020 --- Thousands of metric tons of wasted food could be saved every year with a new monitoring system currently being developed by Italian scientists at the University of Cagliari. It “pinpoints” the expiration of perishable produce, even after a ‘use-by’ date has expired. It aims to check the past exposure to warmth and genuinely tell whether food is unfit for human consumption.

Around 88 million metric tons of food are wasted every year in the EU based on estimated dates for when food items are no longer safe to eat.

A scientific breakthrough
This “technological breakthrough” has been brought to light by Professor Carlo Carbonaro and his research team Their food monitoring device, which relies on photonics, otherwise known as the technology of light.

The technology monitors past conditions that alter shelf life. For example, it tracks historic temperatures of perishable food with a handheld scanner and a sticky label that reacts to ultraviolet light. This creates a historic “heat map” that indicates exposure to warmth.  

Containing a tiny sachet of powder patented by the Italian scientists, the sticky label reacts to the ultraviolet light scanner, indicating the food item’s unique status on a particular day.  

Supply chain workers can then assess the potential expiration date against a set of pre-programmed criteria in real-time to optimize the transport of goods – effectively fine-tuning the food item’s use-by date by the time it reaches a supermarket shelf.

Eighty-eight million metric tons of food is wasted every year in the EU.  “Thousands of tons of wasted food can now be saved every year with our highly accurate optical food monitoring label,” says Carbonaro, lead researcher from the University of Cagliari. 

“The handheld scanner allows us to extract the average temperature of the food. We exploit UV to activate our labels, and then use visible light to excite the Optically Stimulated Luminescence to read its history – extracting an average temperature which is compared to an expected value.”

Changes in temperatures during transportation can affect the shelf life of fruit, for example, so the team can tell instantly whether the foods have been exposed and how likely this will modify the expiration period. 

“We can add a level of assurance even after a food item has passed its use-by date,” adds Carbonaro.

While the innovation project began approaching the technology from a food waste point of view, it soon became apparent that the UV monitoring labels had other beneficial uses.

“Our studies on wine showed that although the expiration period is not necessarily affected by the changes in temperature, the heat can have an impact on flavor, which is an essential criterion for vendors, producers and consumers,” Carbonaro comments. 

Support for researchers
Carbonaro and his team have been supported in taking their innovation to the next level of industrialization by ACTPHAST 4R, a photonics innovation hub designed to give researchers in academic institutes in Europe the chance to turn their breakthrough scientific concepts into industrially-relevant demonstrators.

“ACTPHAST 4R has provided us with the expertise in optics and photonics that is essential to building a demonstrator for our breakthrough concept. ACTPHAST 4R provided open access to Europe’s According to scientists at the University of Cagliari, blanket ‘use-by’ dates could be a thing of the past in Italy. top experts in the accelerated development and deployment of photonics.”

“We also were able to access the cutting-edge equipment and hands-on training in photonics that are essential to developing our scanner and sticky labels, and that are not available to us locally within our university or our region,” Carbonaro further explains. 

The research team also received business coaching to develop their commercialization strategy for their innovations.

“In parallel with our technical development work, we have also been working with prospective industrial users of the innovation to gain their feedback so that we can better understand their requirements and validate the application use cases.” 

We hope to license the technology or create a new spin-off company to bring the innovation to market in the next two years,” he concludes. 

Edited by Elizabeth Green