Food Science

Question 1

What is gelatinisation?

Answer 1

When flour is mixed with a liquid and heated, the mixture thickens

Question 2

What is dextrinisation?

Answer 2

When dry heat is applied to products e.g. bread, it causes the product to brown

Question 3

What is caramelisation?

Answer 3

When the colour of sugar changes from white to brown when heated

Question 4

What is shortening?

Answer 4

When fat is used in rubbed-in mixtures, the finished product will have a short crumbly texture

Question 5

What is aeration?

Answer 5

The process of trapping air into a mixture to cause it to rise

Question 6

What is plasticity?

Answer 6

The ability of a solid fat to soften over a range of temperatures

Question 7

What is emulsification?

Answer 7

The process of using an emulsifier e.g. egg yolk, to prevent a mixture of oil and liquid from separating e.g. mayonnaise

Question 8

What is coagulation?

Answer 8

When the protein in food sets

Question 9

What is foam formation?

Answer 9

A foam is produced when eggs are whisked

Question 10

What is gluten formation?

Answer 10

When making bread, strong flour with high gluten content is used to provide the structure for the bread

Question 11

What is acid denature?

Answer 11

When acids are used to change the shape and structure of protein foods e.g. tenderise meat or provide a soft texture,

Question 12

What is enzymic browning?

Answer 12

When fruit or vegetables go brown

Question 13

What is oxidisation?

Answer 13

When fruit and vegetables are cut open and the cells are exposed to air

Question 14

What is yeast?

Answer 14

A raising agent used in bread making to give the bread lightness and causes it to rise

Question 15

What are chemical raising agents?

Answer 15

They include baking powder, bicarbonate of soda and self-raising flour. They can be used to make bread products rise.

Question 16

How is air used in baking?

Answer 16

Used in whisked sponges, soufflés and meringues to give lightness to the mixture

Question 17

How is steam used in baking?

Answer 17

Causes products that contain a lot of liquid to rise e.g. eclairs, choux pastries

Question 18

Give reasons why we cook food

Answer 18

To destroy bacteria
To make food less bulky
To improve the keeping quality of food
To make it easier to digest
To develop flavour
To destroy natural poisons in food
To have hot food in cold weather
To make it more colourful and attractive
Textures are changed
Variety in the diet
The aroma in food is released

Question 19

How is heat transferred by conduction?

Answer 19

Heat is transferred by contact with heat

Question 20

How is heat transferred by convection?

Answer 20

Heat moves through the convection currents. The hot air rises and cool air falls.

Question 21

How is heat transferred by radiation?

Answer 21

Direct rays pass from the heat source to the food

Question 22

What are the names of the proteins found in wheat which form gluten?

Answer 22

Gliadin and glutenin

Question 23

What happens in meat between 40 and 60 degrees?

Answer 23

The muscle fibres coagulate

Question 24

What happens to meat after 60 degrees?

Answer 24

The fibres in the meat shrink

Question 25

What happens in eggs at 60 degrees?

Answer 25

The egg white begins to coagulate

Question 26

What happens in eggs at 70 degrees?

Answer 26

The egg yolk begins to coagulate

Question 27

What is syneresis?

Answer 27

If eggs are heated too quickly the liquid from the egg separates out and the protein becomes tough.