Food Spoilage Flashcards
What are the causes of food spoilage?
Enzymes, moisture loss (dehydration), contamination of microbes (bacteria, fungi + yeast), physical damage.
What is the role of enzymes in food spoilage?
Enzymes cause ripening, browning of food, and enzyme deterioration.
How do enzymes cause ripening?
Fruit & veg contain enzymes that change colour, flavour, and texture during ripening.
Example: Unripe banana is green, bitter & hard; ripe banana is yellow, sweet + soft.
What is enzymatic browning?
Fruit & veg can turn brown when exposed to air due to the enzyme oxidase reacting with air.
Example: Sliced potatoes, apples, and bananas.
How does enzyme deterioration affect fish?
Enzymes in fish cause deterioration at low temperatures, leading to bad taste and smell.
What are ways to prevent enzymatic food spoilage?
Heat (cooking), blanching, and cold storage (refrigeration).
How does heat prevent enzymatic spoilage?
Cooking food denatures enzymes, stopping ripening and browning.
Example: Stewed apple.
What is blanching?
Blanching is a method that denatures enzymes and stops enzyme activity and spoilage.
What happens to fruits and vegetables after harvesting?
They cannot absorb moisture from soil, leading to dehydration, shrinkage, and wrinkles.
What is microbe contamination?
Microbes like yeast and mould can contaminate food but are usually visible and won’t cause food poisoning.
What is an example of physical damage to food?
Dropping fruit, such as a banana, can cause bruising and spreading.
What are the types of food poisoning (FP)?
Biological food poisoning, chemical food poisoning, bacterial food poisoning.
What is biological food poisoning?
Some foods produce natural toxins that can cause FP if eaten in large amounts.
Example: Rhubarb contains oxalic acid, inhibiting calcium absorption.
What is chemical food poisoning?
Harmful chemicals in food or from packaging can seep into food, causing FP.
What are the effects of pesticides in food?
Pesticides can cause respiratory issues and lead to food poisoning.
What causes bacterial food poisoning?
Pathogenic bacteria contaminating food that is consumed.
What is toxic food poisoning?
Caused by exotoxins produced outside of bacterial cells, with symptoms showing within 2 hours.
Example: Staphylococcus aureus.
What is infectious food poisoning?
Caused by endotoxins produced inside bacterial cells, released after cell death, with symptoms showing within 12 hours.
Example: Salmonella.
