Class 8 Science – Chapter 2
Microorganisms: Friend and Foe
Page 5: Food Preservation

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🍎 What is Food Preservation?

Food preservation is the process of preventing food from spoilage caused by microorganisms such as bacteria and fungi.

Proper preservation helps food last longer and keeps it safe to eat.

🧂 Common Methods of Food Preservation

• Salting: Used for fish, meat, pickles
• Sugaring: Used in jams, jellies, squashes
• Drying: Removes moisture (grains, vegetables)
• Heating: Boiling kills microorganisms

🥫 Chemical Preservatives

Certain chemicals are used to prevent the growth of microorganisms.

• Sodium benzoate
• Sodium metabisulphite

These are commonly used in juices, jams, and sauces.

❄️ Modern Preservation Methods

• Refrigeration: Slows down microbial growth
• Freezing: Stops growth of microorganisms
• Canning: Food sealed in airtight containers
• Pasteurization: Milk heated then cooled quickly

✅ Why is Food Preservation Important?

• Prevents food spoilage
• Reduces food wastage
• Makes food available for longer time
• Protects us from diseases

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📌 Next: Chapter 2 – MCQs & Worksheets