FREEZE INDICATOR

There is a need for monitoring freezing of certain freeze sensitive products, such as fresh blood, certain vaccines, fresh produce and certain chemicals/adhesives to determine if the product has been subjected to a freezing temperature and thus damaged. Freeze indicators based on rupture of a capsule containing water/dye and sucking of color liquids through a capillary, are available commercially. This type of devices are large, complex, difficult to manufacture and expensive. There is a need for a device, which is simple, small, easy to make/use and economical. JP labs has developed such a freeze indicator.

JP Labs freeze indicator is in form a label. When the temperature of the freeze indicator is lowered below the freezing point of water, it undergoes an irreversible color change, e.g., blue-to-red. The device is small (e.g., ~1x1x0.1 cm³). It changes color at a predetermined temperature ranging from 4 to –20^oC and the time required for the color change is varied from a few minutes to several hours. Addition information and slide presentation are provide in our presentation at “Institute of Food Technologists Annual Meeting”, Chicago, IL July 12-16, 2003.