UPM's Shelf Life Guard turns from transparent to blue, informing the processor, distributor, or consumer that air has replaced the modified atmosphere gases within the package. Finland-based UPM said the label would help the food industry to monitor and self-assess their produce's shelf life, allowing them to maintain quality and avoid recalls. It could also be used to give consumers directions on use and product information. Food packaging traditionally uses modified gases to prolong food. UPM Shelf Life would indicate that the food is not fit for consumption due to loss of integrity or damage to the package, the company claimed. Air in a package may cause the quality of a food product to deteriorate. The air may also encourage of growth of unwanted bacterial activity, loss of colour and aroma, unsavoury odours, loss of nutritional value or physical changes like drying and rancidity. The colour change of the packaging label allows the consumer to make a personal assessment of the product based on his or her own sensory findings, and consume the product well before the best before date. "An uninterrupted cold chain and the correct storage of products are the basis of food safety," said Timo Äijälä, a UPM manager for its smart labels unit. UPM Shelf Life Guard has been tested at the Lapin Liha meat factory outlet, the Tampere University Hospital and Wigren meat products at the department store Stockmann in Tampere. UPM's intelligent packaging product family, designed for use in the food industry, also includes Freshness Guard, which signals deterioration in poultry or fish products in modified atmosphere or vacuum packages. Both UPM Shelf Life Guard and the Freshness Guard comply with the European Union's regulations relating to food packaging, the company stated. The company is introducing UPM Shelf Life Guard at the PacTec 2007 fair held in Helsinki Fair Centre from 16 to 18 October.