1. TOPIC 4 Food Processing
Natural Science Grade 6.

2. KEY WORDS Seasonal: Only available at certain times of the year.
Perish:
To go bad.
Brine:
Water to which a lot of salt has been added.

3. TOPIC 4 Food Processing (Big Creative heading, 3 lines)
Skip one page for TOPIC 3’s mind- map.

4. _______ The need for processed food
Most of the food that come in containers are processed food. (Tins, bottles, packets, tubs)
Processed food
Natural food
Processed food

5. Benefits of processed food
Can often be eaten immediately, without having to be cooked.
Saves time because it has less cooking time.
Seasonal food is now available all year round.
Easily perishable food can last longer.
We can eat food that was harvested in other countries.
We can eat many different foods, because we don’t have to rely on what is available close to our homes.

6. Reasons for processing food.
1. To make them edible. 2. To make them last longer. 3. To improve its nutrient value.

7. 1. Processing food to make it edible
Some natural foods cannot be eaten directly from nature.
(Just think of a raw potato)
It can sometimes be dangerous. Fish for example needs some preparation before it can be eaten.
We need to remove the scales, skin and if possible the bones.
Chicken also undergoes processing. (we don’t eat chickens with their feathers). It is very dangerous to eat raw chicken.
By cooking fish and chicken we kill the bacteria that makes you ill, therefore the food will then be edible.

8. 1. Processing food to make it edible

9. 2. Processing food to make it last longer
Fresh food only lasts a certain amount of time.
Processing the food makes it last longer, we call this preserving.
We can freeze, cook, pickle, dry or salt the food to make it last longer.
Canned peaches is an example of preserved food, they can last up to two years in the can. The sauce that comes with the canned peaches form part of the preserving process.

11. 3. Processing food to improve the nutrient value
Some food processing improves the nutrient value, for example the process of fermentation.
Fermentation is a process whereby good bacteria is added to a food type.
The bacteria causes a reaction in the food.

12. For example yogurt. It is made by adding good bacteria to raw milk
For example yogurt. It is made by adding good bacteria to raw milk. A lot of vitamins and minerals are released during this process, thereby increasing the nutrient value of the milk (which has now turned into yogurt).
Many fermented foods contain a higher amount of proteins after fermentation.

13. Nutrient loss during processing
As a rule fresh natural foods contain more nutrients than processed food.
Some vitamins are destroyed by heat. If we cook or boil food, some of the nutrients go into the water. Frozen foods also lose some of their nutrient during the freezing process.

14. _________ Methods of processing food.
1. Combining food:
Different ingredients can be added to the natural foods to improve the flavour, the look or preserve the food.
Tomato sauce is an example of a combined food. It is made up of tomatoes that have been made into a paste, vinegar, salt, spices and water.

15. 2. Cooking:
Heat from cooking kills off bacteria in the food and allows the food to stay edible for longer.
Cooking stops the bacteria from making food go bad.

16. 3. Pickling:
It is when we place food into edible fluid that will kill the bacteria.
This fluid could be brine, vegetable oil, olive oil or vinegar.
The pickling fluid prevents bacteria from growing and stops the bacteria from receiving oxygen, which they need to grow.
(try to do act 4, topic 4 at home)

17. 4. Freezing:
It is often used for vegetables.
Before frozen, vegetables are boiled in water to kill off bacteria and to allow the vegetables to soak up water.
It is quick-frozen in freezers that are much colder and freezes faster than our freezers at home.

18. Fish is also frozen because fish attracts a lot of bacteria
Fish is also frozen because fish attracts a lot of bacteria. It may have little organisms (microbes) that cause diseases.
By freezing fish, the microbes are made inactive. This is why some frozen fish often have a note advising people to cook them from frozen. This kills the frozen microbes before they can become active.

19. 5. Fermenting:
Is when good bacteria is added to food to change its state.
For example yogurt and cheese.
The bacteria in yogurt is very good for your digestive system.

20. 6. Drying:
Drying food has been used since ancient times.
Because dried food is hard on the outside, microbes cannot get inside.
Drying takes away a lot of the nutrients.
It can make the taste more concentrated.

21. 7. Salting:
It is an ancient method to preserve food.
Meat is often covered in salt and then hung to dry, we call this curing.
The salt draws the moisture out of the meat and protects it against bacteria.

23. ______________ Indigenous ways of processing food.
Homework activity:
Watch the video on indigenous ways of processing food and read the section in your textbook.
Make a summary about the video and the information in your textbook.

24. Make a mind map on Topic 4, Food processing.
Homework activity:
Make a mind map on Topic 4, Food processing.