Shelf life means that time period for which Food is eatable by humans. if a Food item remains eatable for one day it means it has one day shelf life. If a Food remains eatable for one year, it means that it has one year shelf life.
We know that fresh Food has very short shelf life. This happens because fresh Food is not secured. It has tiny organisms in it that are known as enzymes. Enzymes are basically the organisms which are responsible for the mature Food. If we will not kill them after plucking the Food from plant they will continue their reaction and will spoil our Food. So we store our food in Refrigerators so that those enzymes cant work and our Food is safe for long time.
Other way to extend shelf life is by use of different chemical, mechanical techniques that can preserve food for long time.
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