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How to Preserve of Foods?


Food can be prevented from spoilage by microorganisms in a number of ways. Prevention of food from getting spoiled using different methods is called food preservation.

Drying of dehydration:- Since microorganisms grow in moist conditions it is important to dry the food items like seeds before storing them. Removing moisture or extra water content . Many vegetables and seeds are dried in the sun to remove moisture from them.

Sweetening and Salting:- Addition of sweet and salt to food items helps in losing water from them. Sweetening is used to make jams, jellies and squashes. Salting is used to prepare pickles, sauces and purees. Fish, meat and chips are also preserved by salting.

Heating:- Heating food items to high temperatures kills microorganisms. Milk is preserved using the technique called pasteurization. In this process milk is first heated to very high temperatures and they cooled rapidly to very low temperatures. This heating and rapid cooling kills the microorganisms. The milk is them packed and sold.

Using chemical preservatives:- Many food items are stored using chemicals like sodium benzoate. These chemicals remove the oxygen content from the food items thus preventing the growth of microbes. These chemical preservatives are used to preserve jams, ketchups and squashes.

Canning:- once the food items are sterilized they are stored in air tight jars and cans to prevent re growth of the microbes. Freezing:- food items like fruits, vegetables, meat and fish can be stored by freezing them in deep freezers. Freezing does not allow microbial growth and keep the food item preserved for a very long time.

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