The temperature sensing device created by Empa Swiss Federal Laboratories for Materials Science and Technology looks and acts like a piece of fruit, down to its shape, size, surface texture, color, and internal composition. The self-powered wireless electronic sensor is surrounded by a solid shell made of polystyrene (a type of plastic), water, and carbohydrates that simulate the fruit’s flesh, according to Thijs Defraeye, a scientist at Empa who is leading the project. Traditional sensors used for this application usually only measure the air temperature in the freight container. To accurately gauge how produce is holding up, though, you need to know the fruit’s core temperature, as a warm inner can lead to spoilage.
The device can be tailor-made for the particular type of fruit, even down to a specific cultivar, like a Braeburn apple or a Kent mango, and it can be packed directly with the fresh produce while in storage or during shipping, says Defraeye. Once the shipment arrives at its destination, the data – things like what the fruits’ core temperature was over time – can be quickly analyzed to determine if there were any problems during the trip.
A fruit spy among mangoes. Empa
In the U.S., an average of 12 percent of fresh fruits and vegetables are lost before making it to the consumer. According to the United Nations’ Food and Agriculture Organization, globally about 1.4 billion tons of food – a value of more than $1 trillion – are lost or wasted each year, about 30 percent of which happens post-harvest (that includes storage and shipping).
Defraeye believes there are a variety of different applications for the sensor all along the supply chain – from greenhouses and orchards, to cold storage and ripening facilities, to the transportation sector – by exporters, importers, wholesalers, and retailers alike.
“They will be able to better pinpoint the location and reason for unexpected quality loss, which is essential for quality claims,” Defraeye tells Modern Farmer in an email.
Initial field tests on the sensors are under way and the researchers are now looking for potential industrial partners to manufacture the devices, which they believe would cost less than $50 per unit.