OnVu ICE time temperature indicator

The OnVu ICE time temperature indicator can be used on food packaging to monitor the cold chain for chilled and deep-frozen food. Manufacturers, retailers and consumers will be able to tell at a glance whether ice-cream, pizza, fish or any other products were kept constantly deep-frozen or should rather be discarded because the cold chain was interrupted significantly.

The label is easy to use: a temperature-sensitive ink is used to print a thermometer symbol on the product label or even, in the packaging line, directly on the packaging. The indicator at the centre of the thermometer is activated for use by means of UV light, which causes it to turn a dark blue colour. From this moment on, the indicator monitors the cold chain.

Acting as a reference, the outer portion of the thermometer is a lighter shade of blue. The cold chain monitor works simply: as long as the centre is darker than or the same as the reference colour, there has not been any significant interruption in the cold chain - the best-before date shown on the packaging remains valid. As time goes by and/or if the cold chain is broken, the colour pales.

The speed of the colour change process and the temperatures that trigger it can be customised individually. On frozen foods, the label stays dark blue as long as the temperature is kept continually below minus 18°C. The higher the temperature rises, the faster the colour changes. This is suitable for foods that keep for a long time when frozen to -18°C.