food preservation

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FOOD PRESERVATION MAKE IT LASTS

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Page 1: Food preservation

FOOD PRESERVATION

MAKE IT LASTS

Page 2: Food preservation

BOTTLING AND CANNINGBottling and canning are

processes of preserving food by heating and then sealing it in an airtight container.

The food is boiled to kill microorganisms and then sealed to prevent other microorganisms from getting in.

Page 3: Food preservation
Page 4: Food preservation

PICKLINGPickling food in vinegar or other

acids, makes it difficult for microorganisms to live. Commonly pickled food include onions, parkias, soya beans and chillies.

Page 5: Food preservation

Sugar can also be used in pickling fruits such as nutmegs, mangoes and cherries.

The concentrated sugar solution used draws water from the fruit thus preventing the growth of microorganisms.

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Page 7: Food preservation

DRYINGA lot of food is preserved by

drying under the sun.

Drying removes most water from food. Most bacteria die or become inactive when the food is dried.

Page 8: Food preservation

Anchovies and dried chillies are examples of dried food

Page 9: Food preservation

A lot of fruit such as raisins, guavas and papayas can be eaten dried.

Page 10: Food preservation

SALTINGSalting is an age-old way of preserving food. The salt draws out moisture and prevents microorganisms from growing. In this process, food such as fresh fish are gutted, washed and coarse salt is rubbed into it.

Page 11: Food preservation

A lot of our local foods are preserved by salting process.

Page 12: Food preservation

VACUUM PACKINGVacuum packing keeps food by sucking air out from its packaging.

Food is thus prevented from spoiling because there is no air.

Page 13: Food preservation

Vacuum paching is commonly used for storing nuts, sliced fish, pickled and dried fruit.

Page 14: Food preservation

COOLING AND FREEZING

Cooling and freezing are the most common forms of food preservation.

Page 15: Food preservation

Cooling slows down the action of microorganisms, thus it takes longer to spoil. It allows fruit from different parts of the world to appear on our supermarket shelves.

At freezing temperature, microorganisms become inactive, thus food cannot spoil when it is frozen.

Page 16: Food preservation

Food like meat, fruit and vegetables are kept in the refrigerator.

Page 17: Food preservation

WAXINGWaxing of fruit and vegetables is also

common. Apples, oranges, eggplants and tomatoes are dipped into liqiud wax to prevent growth of fungi and loss of moisture.

Waxed fruit need to be washed thoroughly or peeled before eating.

Page 18: Food preservation

PASTEURIZATIONPasteurization means heating

food to a certain temperature for some time followed by rapid cooling. Heating at such high enough temperature kills most bacteria. However, it does not affect the taste and nutritional value of the food.

Page 19: Food preservation

Fresh milk, yoghurt drink and juices are pasteurized to make them last longer.

Page 20: Food preservation

BOILINGAs food is heated and cooked, the heat kills

the microorganisms,

Boiling kills most bacteria. However, those not affected by heat will grow when the conditions are suitable.

Boiling kills bacteria

Page 21: Food preservation

SMOKINGSmoking is the process of drying food

with smoke for a long period of time. This method is mainly used for fish, meat and fruit such as banana.

The drying effects of smoke and the chemicals produced from the smoke help to preserve the food.

Smoked banana smoked meat

Page 22: Food preservation

FOOD PRESERVATIONFood preservation is a process of

slowing down food from becoming bad.

Besides making the food lasts longer, preservation also prevents food wastage.

Page 23: Food preservation

Food preservation also allows food to be eaten out of season. It gives variety and nutrition to our diet all year round.

Freeze-dried food are easy to store and transported because they are light and require less space.

Page 24: Food preservation

Durians, rambutans and starfruits can be preserved in different ways.

Instant coffee, milk powder and curry poweder are freeze-dried.

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THE END