An intelligent food wrapping that changes colour if the contents are going bad has been developed by British scientists.
The smart plastic packaging has the ability to detect when meat, fish or salad leaves have passed their use-by date or have been left out of the fridge for too long.
It also alerts householders if sealed packaging has been broken or damaged, putting the contents at risk.
According to scientists, it will help people uncertain about best-before and use-by dates on food - and reassure those who gamble with the dates on meat and dairy produce.
Previously, scientists have developed indicator labels, which are inserted into food packaging. But the new plastic is designed to be part of the wrapping itself.
It works with food such as meat, fish or salad that has been sealed in a "modified atmosphere" where levels of oxygen are reduced and replaced with inert nitrogen or carbon dioxide gases to slow natural decay.
The new plastic is designed to change colour if levels of oxygen rise above a predetermined level.
It also responds to chemical changes triggered by food spoiling.
"At the moment we throw out far too much food, which is environmentally and economically damaging.
We hope this will reduce the risk of people eating food that is no longer fit for consumption and help prevent unnecessary waste of food," the Daily Mail quoted Professor Andrew Mills, who is leading the research at Strathclyde University, as saying.
Mills said the first smart wraps could be in the shops within two years.