food spoilage pg 34/35 Flashcards
most microbes are…
harmless but pathogenic ones spoil food (go off) and cause food poisoning
3different groups of microbes which are
-bacteria
-moulds
-yeast
microorganisms need 5 conditions to grow and multiply which are;
-warm temperature
-moisture
-food
-right pH (not acidic/alkaline)
-time
what will changing the conditions of micro-organisms do
slows or stops the growth of micro-organisms
name examples of how to change the conditions of micro-organisms
-using a fridge to change temperature
-pickle the food in vinegar to change pH
-add salt
name where microbes are found
-soil
-clothing
-food
-equipment
-air
-dirt
high risk foods have …. conditions for bacteria
ideal
whats a hugh risk food
ready-to-eat foods, that if not stored right grow harmful bacteria
-theyre moist and high in protein
name high risk foods
-cooked meat, fish
-dairy products
-gravies, stocks and sauces
-shellfish
-cooked rice
what are enzymes
proteins that act as biological catylsts
ripening
-enzymes cause fruits to ripen affecting the colour, sweetness and taste
name an example of ripening
-bananas are green and firm and enzymes break down starch inside them
-making the banana soft and sweeter
browning
-when slicing fruits oxygen in the air turns the fruit brown. enzymes inside speed up this process
Name 2 methods to slow/prevent unwanted enzymes
-adding an acid
-blanching
explain adding an acid
enzymes work best at a ph and if u put fruit into lemon juice, the acidic conditions stop enzymic borwning