1. Chapter at a Glance

Disha finds her forgotten tiffin box with a spoilt uttapam covered in coloured patches, and becomes “Detective Disha”. Her elder brother explains that the patches are mould, made by tiny living things called microbes. Microbes are everywhere, and some spoil food while others help us.

Disha learns that microbes need moisture, air and the right temperature to grow. Her family preserves food by removing one of these: drying chillies in the Sun, adding oil to pickles, keeping food in the fridge, and making ghee from butter. Salt, sugar, spices and airtight cans also preserve food. Good microbes help make curd and fluffy idli batter, and curd helps digestion.

Disha also learns about eating seasonal fruits, chewing food properly with different kinds of teeth, keeping teeth clean and eating slowly to avoid choking. The mystery is solved: eat right, store food right, chew well and thank the good microbes.

2. Word Meanings

3. Important Topics

A. Why Food Spoils

• Microbes grow on food and change its taste, smell and look.
• Mould, the coloured patches on old food, is a colony of thousands of microbes.
• Microbes are found in soil, water, air, plants, animals and inside us.
• They need moisture, air and the right temperature to grow.
• Eating spoilt food can cause an upset stomach.

B. Ways to Preserve Food

• Ghee lasts without a fridge because heating butter removes its water.
• Clay pots (matkas) keep water cool without electricity.

C. Good Microbes

• They help make curd: a spoonful of old curd added to warm milk.
• They make idli batter rise and become fluffy.
• Curd and buttermilk help digestion when we have an upset stomach.
• Fermented rice (pakhala, kanji) cools the body and is full of good bacteria.

D. My Food, My Pride

• Families pass down food traditions from one generation to the next.
• Seasonal fruits like lychee, mango, amla (winter) and jamun (summer) taste best in their season.
• Local fruits are fresher because they don’t travel far.
• India is the largest producer of millets and pulses, and one of the largest producers of bananas.

E. Teeth and Chewing

• Chewing breaks food into small pieces and releases saliva, which helps digestion.

F. Healthy Habits

• Rinse your mouth after eating and brush regularly.
• Eat fewer sweets to avoid cavities, and visit a dentist for toothache.
• Eat slowly, take small bites and don’t talk or laugh with food in your mouth, to avoid choking.

4. Question-Answers

Very Short Answer Questions

1. What were the coloured patches on Disha’s uttapam?
Mould.

2. What are microbes?
Tiny living things that can be seen only through a microscope.

3. Name three things microbes need to grow.
Moisture, air and the right temperature.

4. Why is oil added to pickles?
To stop air from getting in.

5. Why do fridges keep food fresh?
The cold temperature slows down microbes.

6. What makes idli batter fluffy?
Microbes.

7. Which teeth are used for grinding?
Molars.

8. What is a cavity?
A hole in a tooth.

9. What is India the largest producer of?
Millets and pulses.

10. Name two seasonal fruits.
Lychee and mango (also amla and jamun).

Short Answer Questions

1. Why do some foods spoil faster than others?
Foods with more moisture that are left open to air and warmth spoil faster, because microbes grow quickly in them. Dry, oiled, salted or cold foods last longer.

2. How does drying preserve food?
Drying in the Sun removes moisture. Without moisture, microbes cannot grow, so the food lasts for months.

3. Why does butter need a fridge but ghee does not?
When butter is heated to make ghee, the water in it evaporates. Without water, microbes cannot grow in ghee. Butter still has water, so it needs to be kept cold.

4. How do good microbes help us?
They help make curd and idli batter, and they help digestion. Curd and buttermilk are often given for an upset stomach.

5. Why should we chew food properly?
Chewing breaks food into small pieces and releases saliva, which helps digestion. It also prevents choking.

6. How can we take care of our teeth?
Brush regularly, rinse the mouth after eating, eat fewer sweets and visit a dentist when needed.

Long Answer Questions

1. Explain different methods of food preservation with examples.
Food can be preserved by drying, which removes moisture (chillies, papad, aam papad). Oil in pickles keeps air out (mango pickle). Refrigeration and freezing slow microbes with cold (milk, vegetables). Heating butter removes water to make ghee. Salt, sugar and spices stop microbes (lemon pickle, jam). Factories pack food in airtight cans (canned juice). All these methods remove moisture, air or warmth, which microbes need to grow.

2. “Some microbes are harmful and some are helpful.” Explain.
Harmful microbes grow on food and spoil it by changing its taste, smell and look. Eating such food can make us sick. Helpful microbes turn milk into curd, make idli batter rise and help digest food in our stomach. So we should protect food from harmful microbes and include good ones, like curd, in our diet.

Textbook Exercise Answers (Let us reflect)

1. Why do some foods last for weeks while others spoil in a few days?
Foods that are dry, oiled, salted, sugared or kept cold last longer, because microbes can’t grow easily in them. Moist foods left open in a warm place spoil quickly.

2. Five food items for a two-day trip, and how to keep them fresh.
Sample: Dry snacks like khakhra, roasted chana, fruits like bananas, parathas and a water bottle. Pack them in airtight boxes, keep them in a cool, shaded place and avoid foods that spoil quickly, like curd rice.

3. What if food could not be preserved?
We would have to eat everything immediately. Seasonal foods would not be available all year, a lot of food would be wasted, and people in faraway places or during droughts would not get enough food.

4. Match the food, the preservation method and the product.

What would happen to pickle without oil?
Air would reach the pickle, microbes would grow, and it would spoil quickly.

How can you avoid choking?
Take small bites, chew properly, eat slowly and don’t talk or laugh with food in your mouth.