Let me state that no storage containers in existence is considered airtight in the technical sense. Most manufacturers, including those of well known brands claimed that their plastics containers are airtight – are solely based on “lay-man” terms. This term is highly debatable because there is no standard measurement or classification of airtight. Definition and testing methods varies from different manufacturers. As such, all storage vessel – whether made of metal, glass or any other material – cannot be technically classified as airtight unless it is vacuum. However, such vacuum household food storage containers do not exist.
About 10 years ago, a Japanese manufacturers came up with a clever solution – a plastics container with a seal valve and air pump. It works by pumping air out of the container via a valve to create a vacuum. Although food stored in these containers stay fresh longer than other containers but it will not last for more than 6 months.
Another fact is that most plastics surfaces are porous in nature. If you put a piece of plastics under high magnification, you will see that the surface are full of tiny holes. This also explain why plastics bags used for food packaging are often laminated with several layers – this is to “cover” as many holes as it possibly can.
Therefore, even containers produced by well-known brands cannot keep food fresh for over a year. Most can only last a few months – despite claiming that their containers are airtight. Yes, it is one of those words that is so misleading and yet everyone around the world continue to use.
Popularity: 32% [?]