Useful and Harmful Microorganisms

Food manufacturing

Bacteria - Making cheese & yogurt Yeast - Making bread & tempeh

Production of antibiotics & vaccines

Prevent the growth of disease-causing microorganisms

Decomposition of organic materials

Bacteria - Use to treat sewage & destroy toxic waste in sewage treatment plants

Usage of good bacteria in food

Lactobacillus used in making yogurt

Production of organic fertilisers

Chicken, cow or goat faeces decompose & mixed with sawdust to form organic fertilisers

Microorganisms cause contagious diseases

Conjunctivitis, tuberculosis, tinea & malaria

Microorganisms spoil food

Cause change in texture, shape, smell & taste

Bacteria cause tooth decay

Sugar & starch from food convert to acid

Food poisoning

Bacteria (Salmonella) in spoilt food will multiply & produce toxins in the human intestine

Symptoms of food poisoning

Diarrhea, vomiting & headache