Abstract
In a daily life the most common method for preservation of fresh food are by keeping them at a normal temperature, or by refrigeration or freezing of them.
This experiment was intended to show how the contents of the vitamins and water in frozen vegetables were changed during 12month preservation after freezing the fresh vegetables. The changes in contents of vitamins also were examined in the vegetables refrigerated after freeze-drying. In order to produce frozen, or dried or canned vegetables, the pretreatment which is essential at its initial step, called blanching, must be performed.
It is confirmed by the experiment that there is little loss of vitamins in case of frozen foods, and is understood that the same amount of vitamins in the frozen foods can be expected for one year as at the time of their production if preserved at-24°C.
