Food Spoilage Flashcards
What do enzymes cause fruit to do e.g makes bananas ok to eat
Ripen
What do fruits contain that cause them to ripen
Enzymes
3 sensory properties that enzymes effect when they ripen fruit
Texture
Sweetness
Colour
2 methods that control the activity of enzymes (e.g stopping enzymic browning where the fruit is oxidated and turns brown)
Adding acid e.g dipping fruit slices in lemon juice- enzymes work best at optimum ph so when too acidic it stops the enzymic browning
Blanching- destroys ripening enzymes
What happens when fruit is sliced and exposed to air
Enzymic browning
Oxygen in air turns fruit brown and enzymes speed up the process
What temperature is the danger zone
5- 63 degrees
What temperature is the freezing zone
Below - 18 degrees
What temperature is the chilling (fridge) zone
0-5 degrees
Where in the fridge should raw meat be placed and why
Bottom shelf
Stop any juices/ blood dripping and contaminating other foods with harmful bacteria like salmonella that can cause food poisoning
What happens to bacteria between 5 and 63 degrees (danger zone)
Grows and multiplies rapidly
Optimum temperature for bacterial growth
37 degrees
(Included in danger zone)
Why should hot food be held above 63 degrees
Any lower is in the danger zone where bacteria grows and multiplies rapidly
Therefore avoids bacteria growing on food which could cause food poisoning
True or false, freezing kills bacteria
False
It becomes dormant (stops growing) but becomes active again when the food is defrosted
What does chilling do to bacteria (e.g putting food in the fridge)
Slows the growth but doesn’t stop it
What is meant by ambient foods
Foods kept at room temperature
Use by vs best before date
Use by is about safety
Best before is about quality
Use by date meaning
Given as a safety warning
Date that a high risk food must be consumed by (after this point you may get food poisoning)
What type of foods contain a use by date
Short shelf life
E.g high risk foods