Question

Describe the different methods of Food
preservation​

Answer 1

Chemical Method: Some chemicals prevent the growth of microorganisms in food. These chemicals are used in pickles and jams to preserve them. Salt, acids and oil are also used as food preservatives. Examples: sodium benzoate and sodium metabisulphate.

Preservation by common salt: When a food item is kept in plenty of salt, water from food comes out because of osmosis. It results in dehydration of the food item. Absence of moisture helps to prevent the growth of microbes. Fish, meat and pickles are preserved by adding salt.

Preservation by Sugar: Sugar preserves food by reducing moisture in food. Jam, jelly and squash are preserved by adding sugar.

Preservation by Oil and Vinegar: The layer of oil on top of food prevents oxygen from entering the food. Some microbes do not survive in absence of oxygen. Some microbes cannot survive in acidic environment and thus vinegar is an effective food preservative.

Heat and Cold Treatment: Most of the organisms can survive within a particular range of temperature. When the temperature becomes too low or too high, organisms cannot survive. Heating a food item or freezing a food items thus helps in preservation. In most of the households, milk is boiled twice or thrice in a day to prolong its shelf life. Milk is pasteurized before being packed. Pasteurization involves heating the milk to 70C for about 15 to 30 minutes and is then quickly cooling down the milk. Pasteurization helps in killing the microbes which may be present in milk.Most of the organisms can survive within a particular range of temperature. When the temperature becomes too low or too high, organisms cannot survive. Heating a food item or freezing a food items thus helps in preservation. In most of the households, milk is boiled twice or thrice in a day to prolong its shelf life. Milk is pasteurized before being packed. Pasteurization involves heating the milk to 70C for about 15 to 30 minutes and is then quickly cooling down the milk. Pasteurization helps in killing the microbes which may be present in milk

Answer 2

Answer:

hope it is clear to you please mark as brilliant answer

Explanation:

preservation that means any food or any other products to avoid the microbial growth.

physical methods

Drying

it is oldest method.done by sun drying or air drying

to remove the water from food.

vegetables

fruits

meat

smoking

smoking is a preserving food by exposing it to it smoke from burning

meat, fish.

freezing

to freeze the food products to avoid the microbial growth.

milk ,meat ,vegetables.

pickling

pickling is one the oldest preservation method.

salt or sugar used to mix vegetables are fruits to mixed it

to avoid the microbial growth.

sugaring

it is a traditional method.

it to high sugar and reduce microbial growth and moisture

salting

salt have a alkaline pH to avoid the microbial growth.

it is one of the traditional method.

vinegar

to avoid the microbial growth and avoid the food spilage.

to protect food aroma.

recent methods

radiation

UV radiation are used food preservation method

to kill the spore forming bacteria.

vacuum methods

to vacuum fully remove air from packets to avoid the spore forming bacteria.

gases

the gases to fill the beverages and chips pockets to avoid the microbial growth.

hydrogen gas

carbon di oxide.