Food procressing Flashcards
Food processing
Any change to natural state of food
Food preservation
Any method of treating food to make it last longer.
Micro-organisms need certain conditions to grow. Any removed, food lasts longer.
Conditions required for micro-organism growth
Food Warmth Moisture Oxygen oH (acid/alkaline)
Methods of food preservation
Freezing Freeze drying Drying Pasteurisation Canning Jam making Bottling Preservatives Irradiation
freezing
Very low temps used. Water changes to ice.
Freeze drying
Food frozen, moisture removed.
Drying
Moisture removed
Pasteurisation
Milk heated and cooled rapidly to kill harmful bacteria.
Canning
High temps used. Cans airtight
Jam making
Fruit boiled. High sugar content (chemical preservative). Jars airtight.
Bottling
Very high temps used. Glass jars sterilised & airtight.
Preservatives
Chemicals such as sugar, salt (chemical preservatives)” vinegar, smoke prevent micro-organism growth. They cannot live in high concentration of these substances.
Irradiation
Energy waves passed through food to kill micro-organisms.
Why food is processed
Micro-organisms killed Waste prevented Enzyme activity prevented Adds variety to diet Nutritive value retained Seasonal food available all year Food easier to transport & store