Food Processing Technology


2.5  Food Processing Technology
1. Food processing technology:
Technology Method Example of food products
Cooking Food is processed by heating food using bleaching, frying, grilling, smoking, braising, stir-frying, baking and steaming.
  • Chicken curry
  • Fried fish
  • Grilled chicken
  • Rice
  • Vegetables 
  • Cakes
Fermentation The breakdown of complex substances into simpler substances through bacteria, yeast or other useful microorganisms.
  • Soy sauce
  • Kimchi
  • Tempeh
  • Yoghurt
  • Tapai
Dehydration or Drying Water is removed from food through dehydration or evaporation by drying under the sun, using flame or smoke or in the oven.
  • Dried shrimp
  • Dried squid
  • Dried fish
  • Dried fruits
  • Cereal
  • Mushroom
  • Milk powder
Pasteurisation The liquid is heated to a temperature below its boiling point to kill pathogens and then cooled quickly.
  • Milk
  • Dairy products
  • Fruit juices

Food is kept in cans which are sterilised and heated to a temperature exceeding 115 °C under high pressure to kill microorganisms and their spores.

The air in the can containing the sterilised food is removed before the can is sealed.

The can is then heated again to kill any remaining microorganisms before being cooled quickly.

  • Meat
  • Soup
  • Beans
  • Fish
  • Fruits
  • Sauce
  • Canned milk

Food is kept at a temperature of 0 °C or lower so that it can last longer.

The low temperature in the fridge can

  • stop enzyme action
  • inhibit the growth and reproduction of microorganism
  • Seafood
  • Meat
  • Chicken
  • Fish
Irradiation Food is exposed to ionising radiation such as gamma-ray, ultraviolet rays and X-rays to kill microorganisms.
  • Vegetables
  • Cereal
  • Fruits
Vacuum Packaging

Air is removed completely from the container or plastic bag used to pack the food before the package is sealed tight.

The absence of air in the package prevents the growth of microorganisms in the package and stops food oxidation.

  • Nuts
  • Rice
  • Durian 
  • Vegetables
2. Chemical substances used in food processing and impacts on health
Chemical substance Functions Example Impacts on health
  • Prevents growth and reproduction of microorganisms
  • Reduces food spoilage
  • Makes food last longer
  • Salt
  • Sugar
  • Vinegar
  • Sodium nitrate
  • Sodium nitrate
  • Benzoic acid
  • Boric acid
  • Sulphuric dioxide
  • Cancer
  • Allergy
  • Foetal defects
  • Damages liver and kidney
  • Adds colour to food 
  • Makes food look more attractive
  • Pandan leaf
  • Turmeric
  • Tartrazine
  • Sunset yellow
  • Carmoisine
  • Cancer
  • Infertility
  • Food poisoning
  • Damages liver and kidney
  • Bleaches unwanted natural colour from food
  • Activated carbon
  • Benzoyl peroxide
  • Cancer 
  • Food poisoning
  • Improves the taste of food 
  • Makes food more delicious and fragrant
  • Enhances the natural flavour of food
  • Sugar 
  • Vinegar
  • Vanilla
  • Monosodium glutamate
  • Cancer
  • High blood pressure
  • Heart diseases
  • Mental retardation in children
  • Damages liver and kidney
  • Prevents deposition of granules in liquid food
  • Improves texture and thickens food
  • Starch
  • Gelatin
  • Agar
  • Acacia gum
  • Sweetens food and drinks
  • Honey
  • Aspartame
  • Sorbitol
  • Cancer
  • Diabetes mellitus
  • Allergy
  • Obesity
  • Damages liver and kidney
  • Slows down the oxidation of fatty food
  • Prevents fruits and vegetables from turning brown
  • Ascorbic acid, Tocopherol
  • Butylated hydroxyanisole
  • Retards body growth
  • Damages liver and kidney
  • Rash and itchy skin
  • Emulsifier substances that do not mix 
  • Improves homogeneity, stability and texture of food
  • Lecithin from egg yolk 
  • Pectin
  • Monoglyceride