The potential of intelligent labels

Food poisoning in the US is claimed to take 5000 lives every year and force 325,000 into hospital treatment. Overall, nearly one in four Americans suffers from some form of food poisoning in any year. That is just one country's experience but despite few similar statistics being available globally, food poisoning must be considered a major cause of illness. But now technology, in the form of radio frequency identification (RFID) is in a position to prevent much of this illness by warning when food is bad or bacterial levels in it are approaching volumes that will cause sickness.

Put simply, RFID is a label, not unlike a barcode, that can be attached to a product. On the label is a small radio transmitter and antenna that can send signals over short distances to a special reader where the condition of the product can be determined.

While these tags, or smart labels as they are called, come in a variety of sizes, complexities and operating frequencies, the main drawback to their much wider use has been cost per item. However, developments in electronics, and particularly in miniaturisation, have now brought this cost down to less than 10 cents in some cases and there are high industry hopes that this will fall to single figures.

Currently, smart labels are being driven by the world's major retail groups, including food, at the pallet or case level. These labels offer a more sophisticated alternative to barcodes by enabling individual product information and history to be controlled. They carry more information than barcodes and can be read without contact using radio. The label's typical construction has an RFID tag or inlay consisting of an antenna and a silicon chip on a carrier film incorporated into a self-adhesive label. The first tags to meet the new Generation 2 (Gen 2) standard developed by EPCglobal have arrived with an average 98% yield at below the 10 cents level. With global standards, higher quality and lower cost there is now an incentive for smart label converters to gear up for volume production of the labels and for the retail beverage and food sectors to have the kinds of quality and service they need to invest in RFID.

This will extend from the pallet and case level to individual item tagging. There are still challenges coming from brand owners and retail groups to reduce still further the costs of tags. As a major proportion of the tag cost comes from the label converting process, largely due to the current lack of economies of scale, it will take some time for label costs to fall much more, according to Label Expo in Britain. But there is a danger that the providers of RFID technology will be left way behind unless they start taking matters seriously.

This forthright warning comes from Ray Chappelow, product manager for Dy-Mark, who was speaking at a recent Australian Institute of Packaging seminar on RFID. He acknowledges the value of the barcode that he says has done a remarkable job of remaining current over the many years that technology has evolved.

"RFID will play a significant role in future barcoding and product identification technologies and providers need to become better educated in the technology and its benefits over existing solutions," he says. RFID has evolved into many other uses but it has not yet penetrated the supply chain and collaborative commerce arena to the levels of the barcode. The technology infrastructure to support RFID is still in its infancy relative to barcode support.

"Now, thanks to EPC Global and the development of an industry standard, we expect to see a rapid uptake of this technology into supply chain applications," he says.

RFID and labelling can work in conjunction with each other so that tracking and tracing products can become far more accurate than previously imagined, he says. Knowledge of how the system works is more than half the battle. The challenge now exists to incorporate this understanding of RFID into businesses. For automatic identification and data collection (AIDC) opportunities, smart labels can enhance an existing technology or help create efficiencies where cost centres exist.

Thermal printers have long been used to print labels for tracking items. They produce a quality printed image on a variety of materials at low cost. RFID capabilities are a logical extension of a thermal printer's capabilities. For example, the Datamax I-Class printer was developed to include the ability to encode data onto RFID while simultaneously printing a graphical image - barcode, text, graphics - onto the label. This allows users to incorporate the benefits of RFID into their current data capture applications while developing new systems.

Smart labels add capabilities to data tracking systems not available with barcodes alone. The main benefits are instant identification, no line-of-sight requirement, the ability to update or supplement data on the label and expanded data capability.

Items can be automatically identified once within range of the reader. The tags do not have to be individually scanned due to anti-collision and individual identification capabilities among readers and software.

The technology allows multiple objects to be identified almost immediately, with the background software acknowledging each individual item through a process of elimination. The software supporting RFID and its radio transmission remove the line-of-sight requirement that limits barcodes. Barcodes need a scanner to be directed at them and are often adversely affected my ambient light levels.

With read-write capabilities, data about an item can be updated throughout the product's life. This enables enhanced tracking that exists on the item. Data for upgrading is certainly available within a barcoding system but the updates take place within the host database. With RFID the database remains with the item and in the host system, allowing for a back-up in case problems occur with accessing the host information. RFID tags enable more than 2 Kb of dynamic data to be carried.

"It could potentially be very easy for a user to get oversold on RFID with all the interest surrounding the technology," says Mr Chappelow.

"The technology allows companies to take another step forward towards real-time visibility of assets, people, items and products. Some companies will see great value in moving towards instant identification possibilities." However, RFID is not the only way of ensuring that food does not put people on the sick list. In America, where 76 million of food poisoning cases are reported each year, a company has developed a label that senses spoilage in fresh meat and poultry products. Called 'fresh' it is a stick-on label that is applied to the outside of the wrapped product by the packer, distributor or retailer. The label detects bacteria levels through the wrapping. While the inside of the label is tangerine orange in colour, the product is fresh and safe to consume. When the bacteria count reaches a critical level, the orange turns to grey to indicate spoilage.

Produced by Food Quality Sensor International, the label is due for widespread distribution to the meat and poultry markets and to grocery distributors during this year. Its cost is claimed to be less than 1% of the total package it labels.

Yet other labels are 'smart active' and 'intelligent', which become active when in response to a trigger event (ie, filling, release of pressure or gases, exposure to UV or moisture) and are then able to switch on and/or off in response to external or internal conditions.

These labels can sense, act, react, inform according to activities or conditions and probably offer some of the most important potential benefits to the food supply and retail chain. Other types provide temperature indication for cold foods, oxygen absorbing or scavenging labels which protect against mould growth, moisture absorbing labels along with leakage indicators and time/temperature indicators are all giving ever more information allowing food to be kept fresh for longer.

For the food industry overall, the potential for RFID and high tech labels is enormous. From tagging cattle, sheep, pigs and poultry to tracking manufacturing processes and on to retail outlets where supermarkets would be able to keep track of all incoming perishable goods, these technologies could reduce waste and ensure food poisoning is something for the history books.