The Active & Intelligent Packaging Industry Association (AIPIA) is a treasure chest of knowledge. Here are two gems:
Has the milk gone off in the carton? Are the veges in the can still ok?
Soon, there will be a way to know without opening the container. It's a colour-coded smart tag invented by researchers at Peking University in Beijing. The tag, which will appear on the packaging, can also could be used to determine if medications and other perishable products were still active or fresh.
What it can do: The tag has a gel-like consistency, is inexpensive and safe and can be widely programmed to mimic almost all ambient-temperature deterioration processes in foods according to Dr Chao Zhang, the lead researcher of the study. It can give a reliable indication of the quality of the product that does not depend on the manfacturer, grocery-store owner or consumer knowing if the food has been exposed to damaging temperatures.
The tags are the size of a kernel of corn, and may appear in various colour codes on packaging. In the test configuration, red, or reddish orange, would mean fresh. Over time the tag changes its colour to orange, yellow and later green, which indicates the food is spoiled. Colour changes are detectable across the range between 100% fresh and 100% spoiled.
How it does it: The tags contain tiny metallic nano-rods made of gold and silver. At different stages and phases, the colours change to red, orange, yellow, green, blue and violet. Silver chloride and vitamin C in the tags react slowly and controllably, and over time, the metallic silver gradually deposits on each gold nano-rod, forming a silver shell layer. That changes the particle's chemical composition and shape enabling the tag colour to evolve.
The researchers say tags would be very inexpensive with all the chemicals in it costing much less than one cent — $0.002 is estimated. In addition, all of the reagents in the tags are nontoxic, and some of them (such as vitamin C, acetic acid, lactic acid and agar) are even edible.
Was my delivery left in the truck overnight?
AIPIA member, Thinfilm, is developing something slightly different – a sensor that when incorporated into packaging, will tell consumers, distributors and merchants if food and perishables have been kept at the required temperature all the way through the supply chain. The printed electronics company will introduce its low cost NFC time and temperature sensors by the end of 2014.
Will it add to costs? The development of the sensors follows the company's acquisition of Kovio's printed NFC tag technology. This will be combined with Thinfilm's existing printed systems technology to produce the tags that can be added to products and packaging in a cost effective manner.
Thinfilm's Temperature Label will have a selling price of about $0.50, or just under a dollar with wireless functions. The first version will only feature threshold detection, such as upper and lower bounds. Later products will add more functionality.
Packaging company, Bemis Company, and safety specialist, Brady Corporation, have already signed up to use the new smart labels.
Thinfilm is working now to develop a range of sensors that provide valuable information. Sometime in the future, it will be possible to have a sensor inside packaging that can detect various gases and humidity.
