Frozen food storage temp. rise indicator - with absorbent paper or frozen salt solution acting on soluble dye for visible display of freshness

摘要

A display element indicates by its irreversible change that the max. storage temp. of frozen or deep frozen food has been exceeded. This element which is based on absorbing layers and soluble dyes or on frozen tablets of aq. common salt solns. of various concn. is kept in direct thermally conductive contact with the food and gives a visual indication. This is an inexpensive method of warning the consumer that the food may have suffered damage during storage. It is in direct contact with the food itself and contains only substances which are compatible with human food.