New packaging could detect expired food

USA – Scientists at the University of California are developing food packaging that can detect when food has expired.

The developments have huge potential for application in the dairy industry, including the detection of specific bacteria like E coli, reports the New York Times.

The packaging would rely on the use of transistors made of organic materials, rather than the traditional silicon. This means that much lower temperatures can be used – allowing circuits to be printed on materials including plastic and paper.

One major barrier to using the technology in packaging would be the cost. Development team leader Vivek Subramanian said: “I still have to convince every supermarket in the world to use this thing, even if we do it at under a penny.” The development team expects to be able to produce a prototype printer for the circuits by the summer and is working on the infrastructure needed to support the packaging sensors.

The processing speed of organic transistors is much slower than silicon circuits. Also, organic circuits can become redundant within days or weeks if exposed to air or water.

Organic transistors could also be used in mobile phones, blood tests and anti-counterfeiting circuits on currency.