Food processing and packaging.
Pasteurisation
- process use to preserve milk by killing the bacteria, by French scientist, Louis Pasteur.- heated up to 72C for 13 sec or 63C for 30 min, immediate coolong & packaging.
- does not kill the spores of bacteria
- preserves natural flavour as well as its nutritional value.
Dehydration
- removal of water or moisture from food- dehydrated by blowing hot air frm drying machines.
- some nutrient may be destroyed.
Freeze-drying
- decrease temp to -18C & vacuuming out the icicles formed.
- maintain its colour, taste and texture
Canning
- cheap, shelf life for at least 2 years
- cans heated to high temp of 120C, kill microorganisms & spores.
- additives added, air is drawn out frm the cans n quickly sealed.
1. kill microorganism
- bacteria n fungi r decomposers n grow well in warm n moist conditions.
2. to make food last longer
- micro r killed when food is being processed. preserved n last longer.
3. help in packaging the food 4 easy transportation
4. to ensure a constant supply 4 food.
5. provide consumers wif wider choice of food production.
6. help in digestion.
Processed food
- low in fibre, antioxidant, vitamins & mineral content.- contain food additives.
- transported over long distances n kept over a period of time.
foods tht r altered, manufactured in factories n packed in plactic bags, boxes, cans, jars n bottles.
- eg. frozen food, canned food, biscuit, bread, milk, cheese n choc.
Unprocessed food.
- natural form- high fibre, antioxidant, vitamin n mineral content.
- do not contain food additives
- spoilt easily
-eg. fresh fruit, vege, herbs, meat.
Improve food production
Due to :
- increases of world population, increases demand 4 food.- increase quantity to vercome starvation.
Use of quality breeds
produce larger quantity of quality yields in short period of time.a. tenera - the variety of oil palm tht
= cross betw the Pisifera n Dura varieties
= has thick mesocarp, thin shell n large kernel
= able to produce more palm oil
b. Exotica - variety of papaya tht
= cross btw Hawaiian Solo n Subang 6 varieties
c. Masmadu - variety of maize tht
= cross btw Taiwan n Mexican varieties
= sweet fruits
= crop is more resistant to diseases, has shorter fruiting period n produces high yield.
d. Mafriwal - quality breed of cattle tht
= cross btw Feiesien n Sahiwal
= can produce more milkn meat.
= suited to local condition
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