NCERT Solutions for Class 5th The World Around Us Chapter 3 The Mystery of Food
Updated on 2026-09-19
About this chapter
Food spoils because tiny living things grow on it. Disha's uttapam sat in a closed tiffin box for three days. When she opened it, it smelt bad and had coloured patches. Her brother Aditya told her the patches were mould . Mould is made of thousands of microbes living together. Microbes are living things so small that you need a microscope — a special instrument that makes tiny things look big — to see even one of them. Microbes are everywhere. They live in the soil, in water, in the air around us, on plants, on animals, and inside our own bodies. That is Finding #1 in Disha's notebook. Not all of them are harmful. Some spoil our food. Others are good microbes — they turn milk into curd, make idli batter fluffy, and help our stomach digest what we eat. Microbes need three things to grow: mo
- Food Spoilage
- An upset stomach
- Why do some foods spoil faster?
- Why food gets spoiled
- What do microbes need to grow?
- Food Preservation
- Other things that are dried
- Items made from mangoes
- Drying tomato slices in sunlight
- Pickling and Oiling
Quick revision
| Word | What it means | Where it appears | An everyday example |
|---|---|---|---|
| Microbe | A living thing so tiny that you need a microscope to see it | Mystery #1, page 41 | The green-black growth on an old roti |
| Mould | A patch made of thousands of microbes growing together on food | Page 41 | Coloured furry patches on stale bread |
| Spoilage | Food going bad — its colour, smell and taste change and it is not safe to eat | Food Spoilage, page 40 | The uttapam left in the tiffin box for three days |
| Moisture | The water present inside a food | Finding #2, page 43 | The wetness you feel inside a fresh chilli |
| Drying / Dehydration | Taking the water out of a food, usually by keeping it in the Sun | Finding #3, page 44 | Chillies dried on a mat to make chilli powder |
| Pickling | Keeping food in salt, spices and oil so that air cannot reach it | Pickling and Oiling, page 45 | Paati's jar of mango pickle |
| Refrigeration | Keeping food cold in a fridge so that microbes grow very slowly | Refrigeration and Freezing, page 45 | Milk and vegetables in the fridge |
| Freezing | Making food so cold that it turns hard, and microbes stop growing | Page 45 | Peas kept in the freezer |
| Airtight | Sealed so tightly that no air can get in | Page 47 | A sealed can of juice |
| Fermentation | Good microbes working in food and changing it — making it sour, soft or fluffy | Finding #7, page 48 | Idli batter rising overnight |
| Good microbes | Microbes that help us make food and help us digest it | Page 48 | The microbes in curd and buttermilk |
| Seasonal fruit | A fruit that grows only in one season of the year | Finding #9, page 50 | Lychee in the rains, amla in winter |
| Saliva | The watery juice made in the mouth; it wets food and starts digesting it | Finding #10, page 52 | Your mouth watering at the smell of food |
| Types of teeth | Incisors cut, canines tear, premolars crush, molars grind | Types of teeth, page 51 | Biting a guava with the front teeth |
| Cavity | A hole in a tooth | Oral Hygiene, page 52 | A toothache the dentist fills up |
| Choking | Food getting stuck in the throat when it is swallowed in a hurry | Finding #13, page 52 | Gulping food while talking or laughing |
Exercises
- Food Spoilage — Mystery #1 Page 41
- An upset stomach — Think Page 42
- Why do some foods spoil faster? — Mystery #2 Page 42
- Why food gets spoiled — Write Page 42
- What do microbes need to grow? — In-text Question Page 43
- Food Preservation — Mystery #3 Page 43
- Other things that are dried — Write Page 44
- Items made from mangoes — Activity 1 Page 44
- Drying tomato slices in sunlight — Activity 2 Page 45
- Pickling and Oiling — In-text Question Page 45
- Pickle without oil — Discuss Page 45
- Refrigeration and Freezing — In-text Question Page 46
- Food preservation in your family — Activity 3 Page 46
- How are Idlis made? — In-text Question Page 47
- Indigestion and Home Remedies — Think Page 48
- A Visit to the Vegetable Market — Activity 4 Page 49
- Seasonal fruits and vegetables of your region — Write Page 50
- Chew Right! — In-text Question Page 50
- Chewing, and naming the types of teeth — Activity 5 Page 50–51
- Teeth and Chewing — In-text Question Page 51
- The Danger of Choking — Write Page 53
- Closing questions — Let us reflect Page 53–54