food safety Flashcards
what are the conditions needed for microorganisms to grow and multiply
-warmth
-moisture
-food
-pH
-time
how can you limit the growth of microorganisms
-use a fridge
-put the food in vinegar
-add salt
what are examples of high risk foods
-meat, fish and poultry
-dairy products (eggs, cheese etc.)
-stocks
-shellfish
what are enzymes
biological catalysts
what is a biological catalyst
something that speeds up a chemical reaction
how do enzymes affect ripening
-enzymes in fruit help them to ripen, affecting the colour, sweetness and texture
how do enzymes affect browning
-when fruits are sliced, the oxygen turns the fruit brown
-enzymes speed up this process
how can you stop an enzyme from working
-add an acid like lemon juice
-blanching
how do mould and yeast spoil food
-yeast ferments sugars
-moulds change the look of foods
what temperature should you cook/reheat food at
75 degrees
what temperature range is classed as the ‘danger zone’
5-65 degrees
what is the ‘danger zone’
the temp. range where bacteria can grow and multiply the fastest
what temperature range slows down the growth of bacteria
-0-5 degrees
what happens when food is stored at freezing temperatures (-18)
-bacteria becomes dormant
-shelf life is extended
what is the optimum temperature for bacteria to multiply
37 degrees
what temperature should fridges be kept at
0-5 degrees
what temperature should freezers be kept at
-18 degrees
what are ambient foods
foods that can be safely stored at room temp.
how can you extend shelf life of some foods
-freeze drying
-canning foods
-vacuum packing
-using chemicals
what is the use-by-date on foods
a date mark on food which is a safety mark for when the food is likely to be unsafe to eat
what is the best before date on foods
date mark that tells you when the food is expected to deteriorate in quality
how does cross-contamination happen
-other foods
-equipment
-people
-pests
how can you get food poisoning
by eating contaminated food containing pathogenic bacteria
how can you control bacteria
-pasteurisation - milk is heated at 72 degrees for 15 seconds to kill pathogenic bacteria
-vaccinations
