C1 Plant Oils

Question 1

List 3 things that plant oil can be extracted from.

Answer 1

Fruit, seed and nut

Question 2

How are plant oils extracted?

Answer 2

Pressing or steam distillation

Question 3

Why are plant oils used in foods?

Answer 3

Provide energy and nutrients

Question 4

Why are plant oils used as fuels?

Answer 4

Give out energy but are renewable

Question 5

Why are vegetable oils used in cooking?

Answer 5

Higher boiling points so cook food at a higher temperature and so faster

Question 6

What is the disadvantage of cooking with vegetable oils rather than water?

Answer 6

Increases the energy content of the food

Question 7

Give benefits, drawbacks and risks for using vegetable oils to produces fuels like biodiesel

Answer 7

No modification of engine needed

Can be mixed with ordinary diesel

Less polluting as carbon neutral

Biodegrades

But lot of land is used instead of for food

Also increased use of fertilisers and GM crops

Question 8

Why does biodiesel produces no carbon dioxide overall?

Answer 8

Carbon dioxide used in photosynthesis is released during burning

Question 9

Do oils dissolve in water?

Answer 9

No

Question 10

What is an emulsion?

Answer 10

Mixture of 2 immiscible liquids

Question 11

What special properties do emulsions have?

Answer 11

Thicker texture, coating ability and better appearance

Question 12

What do emulsifiers do?

Answer 12

Stop the emulsion from separating

Question 13

Draw and label an emulsifier.

Answer 13

Question 14

How does an emulsifier work?

Answer 14

The Hydrophilic head is attracted to the water and the hydrophobic tail is attracted to the oil

Question 15

What does hydrophilic mean?

Answer 15

Attracted to water

Question 16

What does hydrophobic mean?

Answer 16

Attracted to oil

Question 17

Give a disadvantage of using emulsifiers?

Answer 17

People could be allergic to additives

Question 18

Vegetable oils are unsaturated what does this mean?

Answer 18

Contains double bonds

Question 19

How can unsaturation be tested for?

Answer 19

Bromine water goes colourless

Question 20

What 3 things are needed to harden vegetable oils?

Answer 20

Hydrogen, nickel catalyst, 60⁰C

Question 21

What is the process of hardening vegetable oil called? Why?

Answer 21

Hydrogenation

Question 22

How does hardening vegetable oils change the melting points?

Answer 22

Makes them higher as solid at room temperature

Question 23

Give 2 uses of hardened vegetable oils.

Answer 23

Cakes and pastries and as spreads

Question 24

Too much dietary fat and not enough exercise can lead to what?

Answer 24

Obesity

Question 25

Give 2 problems that saturated fats can lead to?

Answer 25

Heart disease and stoke