The document discusses food spoilage caused by microorganisms like yeasts, molds, and bacteria, as well as the preservation methods such as cooling, pickling, and drying to prevent wastage. It also narrates a story about two brothers making 'mamidi tandra' (a type of mango candy) with their mother's guidance, emphasizing the effort and time involved in food preservation. The text illustrates the importance of food management and experimentation in understanding the spoilage process and preservation techniques.

1. MANGOES AROUND THE YEAR
ENVIRONMENTAL STUDIES
CBSE-V

2. Children in this lesson we are going to learn about Spoilage and
wastage of food,preservation of food(drying and pickling).

3. Food spoilage means the original nutritional value, texture, flavour
of the food are damaged, the food become harmful to people and
unsuitable to eat.

4. There are three types of microorganisms that cause food spoilage --
yeasts, moulds and bacteria.

5. Yeasts:
yeasts and moulds can thrive in high acid foods like fruit, tomatoes,
jams, jellies and pickles.

6. Bacteria:
Bacteria are round, rod or spiral shaped microorganisms. Bacteria
may grow under a wide variety of conditions. There are many types
of bacteria that cause spoilage.

7. Fungal Spoilage: Blue mould rot in tomato caused by Penicilliumi.
Watery soft rot in apple caused by Sclerotinia sclerotiorum.
Bacterial Spoilage: Soft rot in tomato caused by Erwinia carotovora.

8. Enzymes:
Enzymes are proteins found in all plants and animals. If uncooked
foods are not used while fresh, enzymes cause undesirable changes in
colour, texture and flavour. Enzymes are destroyed easily by heat
processing.

9. Oxidation by air:
Atmospheric oxygen can react with some food components which
may cause rancidity or color changes.

10. Microorganisms, specifically bacteria, molds, and yeasts, can cause
food to spoil. For example, microorganisms that break down fats in
unsalted butter can cause it to become rancid. Bacteria that breaks
down protein in meat (proteolytic bacteria) and results in foul odors.

11. Biji returned the bread:
Aman’s Biji went to the market to buy bread. The shop was very
crowded. The shopkeeper picked up a packet of bread and gave it to
Biji. She looked at it and returned it immediately.

12. How does food get spoilt?
The whole class can do this experiment together. Take a piece of
bread or roti. Sprinkle a few drops of water on it, and put it in a box.
Close the box. See the bread or roti everyday until you find some
changes on it.

13. So children the food gets spoiled easily. Bacteria and fungi grow well
at room temperature in the presence of moisture. Cereals and pluses
do not get spoils easily as there is no moisture in them.

14. PRESERVATION OF FOOD:
Food can be preserved by the following methods. We can
stored food by this following five methods.
1. Cooling or Refrigeration
2. Jellying
3. Pickling
4. Drying or Dehydration
5. Tetra packing
6. Canning

15. Food preserved: Food preserved helps in preventing wastage of
food from the spoiling. It also helps us to store food and use it when it
required whole the year. All preserved foods have a shelf life. While
buying and using preserved food, we should check the expiry date
mentioned at the label of the product.

16. Summer treat – Mamidi tandra:
Chittibabu and Chinnababu live in Atreyapuram town in Andhra
Pradesh. The brothers spend the summer holidays playing in the
mango garden, when the trees are full of fruits. They also like to eat
unripe mangoes with salt and chilly powder.

17. At home, their mother cooks unripe mangoes in different ways. She
also makes many kinds of mango pickles. The pickles last through
the year until the next mango season. One evening, while having
food Chinnababu asked, “Amma, we have so many mangoes. Make
some mamidi tandra (aam papad) from them.”

18. Mamidi Tandra:
Their father said, “Making mamidi tandra needs four weeks of
hardwork. If you both promise to help us everyday for the next four
weeks, we can together make the mamidi tandra.”

19. Both the brothers quickly agreed to help. The next day both the
children went to the market with their father. They brought a mat
woven from the leaves of a palm tree. Poles of casuarinas tree, string
made of coconut husk. Some jiggery and sugar. Amma found a
sunny place in the back yard. Both the brothers made a high plat
form by using poles. They spread out and tied the mat on that
platform.

20. Then chittibabu crushed the gur(jiggery) till there were no lumps.
They added the jiggery and sugar in equal amounts to the pulp.

21. China babu mixed the jaggery and sugar well with a big spoon.
Amma spread this pulp into a thin layer over the mat. The thin layer
was left to dry in the sun. in the evening they covered mat with a
clean saree to avoid any dust.

22. The next day they again took out some mango pulp. They added
jiggery and sugar into the pulp. Then they spread the pulp over the
previous day’s layer. This work was given to both the brothers. Both
of them together spread many layers over it.

23. For the next four weeks they hoped that it would not rain. For four
weeks, they added layer after until the jelly grew four centimeters
thick and looked like golden cake.

24. After some days amma said.”Te mamidi tandra is ready, we can take
it out and cut it into pieces tomorrow.” The next day, the mat was
brought down from the platform.

25. Mamidi tandra was cut into small pieces. The brothers tasted it, it
was tasty. Chinnababu said. ”wow, how tasty! After all we have also
helped in making it.