Topic 2 Flashcards
What happens at the first stage of making yoghurt?
The milk is homogenised then pasteurised at 85-95°c to destroy micro-organisms
What are the 4 different types of raising agents?
Chemical, mechanical, physical, biological
Examples of a chemical raising agent
Cream of tartar
Bicarbonate of soda
Baking powder
Examples of mechanical raising agents
Beating
Folding
Creaming
Whisking
Examples of physical raising agents
Moisture(steam)
Examples of biological raising agents
Yeast
What 2 raising agents make baking powder?
Cream of tartar + bicarbonate of soda
Protein definition
Long chain of amino acids
How many amino acids are there?
21
How many essential amino acids do adults need?
8
How many essential amino acids do children need?
10
What does HBV stand for and mean?
High biological value-contains all the essential amino acids
What does LBV stand for and mean?
Low biological value-doesn’t contain all the essential amino acids
Examples of HBV foods
Fish Milk Meat Soya beans Cheese Quinoa
Examples of LBV foods
Sunflower seeds Bulgur wheat Bread Brazil nuts Lentils Beans
3 functions of proteins
Energy
Growth
Repair
Describe what can happen if you are deficient in protein?
Fatigue, weakness, stop growing, lose hair, more likely to get an infection/other illnesses (kwashiorkor)
Describe what can happen if you have excess protein
Too much nitrogen, which is in protein can affect the liver and kidneys, which can lead to liver and kidney damage or failure
Non-pathogenic definition
Micro-organism not harmful to humans and doesn’t cause food poisoning
Homogenised definition
Forcing milk through a fine sieve to break up the fat into tiny droplets
Pasteurised definition
Heating to 72°c for 15 seconds
Blue cheese making differences to normal cheese
- They poked holes in the cheese so that air can get inside and created mould in the cheese
- They added blue mould to make the cheese
- The didn’t press the cheese, they let the whey drain naturally using gravity
- They didn’t add the rennet at the start
- Curds are taken out of the moulds and allowed to continue to drain during the ripening process
What are micro-organisms and where are they found?
They are tiny forms of life and include; bacteria, moulds, yeasts
They are found in many places- water, soil, air, dust, people, animals, sewage, food, etc.
What are the 5 conditions micro-organisms need to multiply?
- the right temp
- moisture
- food
- time
- the right pH
What are enzymes?
They are natural substances (most are proteins) found in food and all living things. They are called biological catalysts.
What do enzymes do?
Enzymes cause fruits and vegetables to riled, change colour, texture, flavour e.g bananas, eventually breaking down the cells and tissues in them. They also cause tissues of meat and fish to break down once an animal has been killed.
How can we control the action of enzymes?
Enzymes are proteins, so their cation can be controlled by causing them to denature - using heat or adding an acid