Food Science

Question 1

Is protein denaturing permanent

Answer 1

Yes

Question 2

What are the 3 way of denaturing a protein

Answer 2

Physical
Heat
Acid

Question 3

How do you physical denature a protein

Answer 3

• whisking foam, protein starch, air gets trapped (aeration)
• kneading gluten is formed when flour is mixed with water, gluten coils, which can stretch and bend, elasticity

Question 4

How does temperature denature a protein

Answer 4

• cooking/heat

Question 5

How does acid denature a protein

Answer 5

• marinate and tenderise meat changes the state and structure

Question 6

What is coagulation

Answer 6

Water traps within a protein (egg)
Over cook = tightens strands and water squeezed out

Question 7

How can carbohydrates starch changed through food science

Answer 7

Gelatinisation
Dextrinistation

Question 8

How can carbohydrates sugar change due to food science

Answer 8

Caramelisation
Maillard reaction

Question 9

What is gelatinisation

Answer 9

• thickening of a sauce
• at room temp start g is suspended - sinks unless stirred
• when heated bonds of the starch molecule break water enters and swells, bursts
• 60°c swelling
  -80°c burst
  -100°c won’t get thicker

Question 10

What is dextrinisation

Answer 10

Starch breaks down into smaller molecules (dextrins)
Cooked with dry heat
Toast

Question 11

What is caramelisation

Answer 11

Sugar breaks down at high temperatures
Goes runny then eventually hard
Adds sweetness to desserts
Occurs in savoury foods as well (onion)

Question 12

What is Millard reaction

Answer 12

Reaction between protein and sugar in Derry heat
Colour and flavour
Roast chicken

Question 13

What are the 4 things that can happen to fats & oils in food science

Answer 13

1. Aeration
2. Plasticity
3. Shorting
4. Emulsification

Question 14

What is aeration

Answer 14

When fat is beaten with sugar
Creaming method air is trapped in the fat and sugar

Question 15

What is plasticity

Answer 15

Ability to spread and mould fats at room temp
Fats contain triglycerides (3 fatty acids & one glycerol)
Different triglycerides melt at different temperatures
Higher plasticity = easier spread
Unsaturated = high plasticity (liquid), saturated = low plasticity (solid)

Question 16

What is shorting

Answer 16

Rub fats into flour, give a flour a water proof coating
Prevents long gluten strands forming
Short texture
Can’t be stretchy

Question 17

What is emulsification

Answer 17

An emulsion = oily and watery liquids
Mixes when stored the separates out
Some foods we need them to mixed
Add an emulsifier to this (e.g. egg)
Hydrophilic like water (binds to water)
Hydrophobic don’t like water (binds to oil)