Food is the basic necessity of man and it is very valuable for his healthy existence. However most foods for consumption undergo deterioration and spoilage. In order to come over this problem fresh foods have to be preserved, moreover when food is available in plenty it can be preserved for future consumption. Foods such as fruits and vegetables have a short growing season and preservation makes them available for use throughout the year and avoids wastage .Food preservation can be defined as science that deals with. The process of prevention of decay or spoilage of food this allowing it to be stored in a fit. Condition. preservation of food increases the shelf life of foods and thud ultimately ensures its supply during times of scarcity and natural drought. Importance of food preservation no food will stay indefinitely in its natural form, All natural foods are alive and like all other living material they are also subjected to the process of decay and deterioration. These gradual changes I fresh foods are part, the due to chemical changes in the living protoplasm of the food itself usually catalyzed by the cell enzymes and part, the due to changes caused by minute organisms which get Into the foods from outside factors.
Meat fish, eggs may become petrified. Fats go rancid milk goes sour, fruits go mould or ferment, vegetables become rotten cereals go muddy or germinate because. Of the action of enzymes, all natural foods are slowly and continuously changing. The appearance, smell. Flavors and value of foods are generally being altered. Preservation of food concentrates on the prevention or slowing down of these changes. Methods of preserving the food. A perusal of the history of food preservation had its origin from time immemorial salting. Of meat ,fish and vegetables was the oldest method of preservation. Pickling in salt and vinegar sun drying and preservation of fruits and vegetables in sugar and honey are other methods used caning in sealed food containers subjected time high temperature was started in 1810. Louis pauster discovered that microbes Were the main cause for spoiling and introduced a new method. Called Pasteurization to the world, All the methods used for preventing the cause of food spoilage, when spoilage organisms are destroyed a more permanent preservation is achieved.