Proteins Flashcards
What are roles of protein?
- makes the body grow
- maintains the body
- gives a bit of energy
What is protein made up of?
Amino acids
What are amino acids made up of?
Peptides (polypeptide chain)
What are the 4 stages of folding in protein molecules?
Primary, secondary, tertiary, quaternary
Name an essential amino acid (9)
Leucine, isoleucine, valine, threonine, methionine, phenylalanine, tryptophan, lysine, histidine
Name a non-essential amino acid (11)
Alanine, glutamine, arginine, glycine, aspartame acid, proline, asparagine, serine, cysteine, tyrosine, glutamic acid
What is an LBV protein?
Low Biological Value protein - lacks an essential amino acid - found in plants
What is a HBV protein?
High Biological Value protein - provides ALL essential amino acids - found in meat, poultry, milk, cheese and soya beans
Give an example of protein complementation
LBV + LBV = HBV
Beans on Toast
Peanut butter on Wholewheat bread
What is a novel source of protein?
Protein that is suitable for vegetarians - Soya, Miso, Tofu, Mycoprotein
Where is ovalbumin found?
Egg white - protein
Where is gluten found?
Wheat - protein
Where is collagen found?
Meat - protein
Where is caseinogen found?
Cheese - protein
Where is Lactoglobulin found?
Milk - protein
What is denaturation?
When the chemical bonds that hold protein together are broken - changes from temperature and pH level
What are examples of denaturation?
Heat - frying/ boiling eggs
Acid - Lemon juice to cream / marinating meat
Air bubbles - whisking into a sponge
Mechanical Agitation - egg whites for meringue
What is coagulation?
Proteins ability to coagulate in eggs
Used in quiche, hold breadcrumbs etc
What happens when you overcook a protein?
Syneresis- eggs - dry + watery
Meat/Fish - dry + chewy - tighten up + squeeze out any water left
What is a deficiency of protein?
Protein Energy Malnutrition (PEM)
Kwashiorkor, Marasmus
What is a minor lack of protein?
Hair loss/ thinning
Brittle nails
Dry skin
Muscle weakness
What is an excess of protein?
Be used as energy instead of growth and repair
DRV of protein is…
4kcal per 1g of protein
15 - 18 Male - 55g Female - 45g
19-50 Male - 55.5g Female - 46g
During pregnancy + 6g
During lactation + 11g
Name foods high in protein
100g salmon - 20g
2 eggs - 13.2g
100g steak - 32.1g
100g chicken breast - 31.2g
150g Tofu - 26.9g
