FOOD PRESERVATION COMPLETE

2. Preservation usually involves preventing
the growth of bacteria, yeast, fungi and
other micro organisms.

3. “A process by which foods like fruits and
vegetables are prevented from getting
spoil for a long period of time. The colour,
taste and nutritive value of food is also
preserved”

5. 1. Presence of microorganism
Situations for the appropriate growth of micro
organisms-
 Food having high moisture content
 Air around the food containing
microorganisms
 Foods kept for long time at room
temperature
 Skin of fruits and vegetables getting
damaged
 Foods with low salt, sugar and acid content

6. 2. Presence of enzymes

7. 3. Insects ,worms and rats

8. 1. Removal of microorganism or
inactivating them
This is done by removing air, water,
lowering or increasing temperature,
increasing the concentration of salt or
sugar or acid in foods.

9. 2. Inactivating enzymes
-by changing conditions such as
temperature and moisture
3. Removal of insects, worms and rats
-by storing foods in dry, air tight
containers

11. 1. Drying –removing the foods water
Sun drying
Commercial drying

12.  Conventional; - heat
 Vaccum; - pulls the water out
 Osmotic;- water drawn out by osmosis
 Freeze drying; - ice crystals vaporize
 Cure –to preserve foods through the use of
salt and drying, sugar, spices or nitrates may
also be added

13. Vinegar
Edible coating-natural wax, oil, petroleum
based wax

15. The elimination of all micro organisms
through extended boiling or through the
use of certain chemicals.

16. Refrigeration
Freezing

17. Pasteurization- heat liquids to 160 degree
celsius for 15 seconds
Ohmic heating- electrical current is passed
through the food generating enough heat
to destroy micro organisms.

18. Low doses of gamma rays, x rays, or
electrons

19. Exposes food to intense, very brief flashes
of light which disrupt the cell membrane of
bacterial cells.

20. Inactivates food borne micro organisms at
low temperature

21. Uses ultra high pressure to inhibit the
chemical process of food deterioration.

22. Ozone is commercially produced by
exposing oxygen to electrical current.
Ozone is an effective disinfectant

23. Foods are packaged airtight by a
commercial sealing process