Preservation Of Food
To preserve food means is to slow down the activity of enzymes and microbes that spoil the food.
They cannot survive in acidic conditions, in high temperature or in high salt or sugar concentrations.
Different techniques are used in different food items.
To preserve tomatoes, first make puree of tomatoes and put it in freezer. For easy use, add puree in ice tray and use whenever required.
Açtion of bacteria reduces and enzyme activity slows down with freezing.
In boiling water, blanch the vegetable. By blanching, microbes and enzymes activities slows down.
Herbs such as mint leaves, coriander leaves mixed with oil to limit the activity of enzymes.
Stem of the bunch of bananas wrapped in plastic wrap. Because of this, ethylene gas which is produced in the ripening process is trapped in stem so that it does not reach to other parts of the bananas.