food spoilage Flashcards
What temperature is the danger zone?
5-63C
How often does bacteria duplicate?
every 20 mins via binary fission
How can you prevent cross contamination?
-wash hands
-wash fruit and veg
-cover cuts with blue plasters
-use coloured chopping boards
-store foods in the correct positions in the fridge
Examples of temperature control to prevent bacterial growth
chilling
-freezing
-canning
-pasteurization
-cook-chill/ freeze
How does removing liquid reduce bacterial growth?
no water for reproduction (drying, dehydration)
What core temperature should foods be cooked to?
75C
What temperature should food be stored in the freezer?
-18C
What is a foods shelf life in the freezer?
3 months - sensory qualities begin to deteriorate due to freezer burn
Thawed food should…
never be refrozen - lose track of time, high risk
How does freezing foods help preserve them?
microorganisms become inactive - e.g. ready meals, frozen meats
How does drying foods help preserve them?
microorganisms need moisture to reproduce and duplicate - e.g. dried milk, pot noodles
How does removing air from food help preserve it?
most microorganisms require oxygen to reproduce - vacuum packaging, cans, jars (e.g. pringles, fish, meat)
Give 4 examples of pathogenic bacteria.
Salmonella, E. Coli, Campylobacter, Staphylococcus
How can food be preserved at home?
-freezing
How can food be preserved using commercial methods?
-vacuum packaging
-sterilising
-drying
-pickling/ jam making
