Chapter 5: Lipids

Question 1

What are lipids classified as?

Answer 1

• Fats

- Oils

Question 2

Uses of lipids?

Answer 2

• Energy stores
• Muscle fuel
• padding from shock
• insulation
• cell membrane
• sensory appeal
• nutrient

Question 3

What are the recommendations from fat?

Answer 3

20-35% energy from dietary fat
<10% from saturated fat
<1% from trans-fat

Question 4

What are the uses of fat?

Answer 4

• low saturates and trans fat helps reduce heart disease

- unsaturated fat reduces blood clotting

Question 5

What are the essential polyunsaturated fatty acids?

Answer 5

• omega 6 (linoleic acid)

- omega 3 (linolenic acid)

Question 6

What is the structure of triglycerides?

Answer 6

• 3 fatty acids + glycerol

- fatty acid: hydrocarbon chain with carboxylic group

Question 7

What are the chain length classifications?

Answer 7

Short: <10 carbons
Medium: 12-14 carbons
Long: >16 carbons

Question 8

Describe the chain lengths

Answer 8

no double bonds: saturated fatty acids (solid at rtp) (coconut and palm oil)
double bonds: unsaturated fatty acids (mono if one) (canola)
>2 double bonds: polyunsaturated (plant and fish oil)

• trans and mono are solid at rtp
• oils contain unsaturated
• CIS is when H is in the same position and TRANS is when H is one up and one down
• pork fat is called lard and beef fat is called tallow (both solid)

Question 9

What is hydrogenation?

Answer 9

• Margarine
• removing C=C bonds by adding hydrogen
• creates trans-fatty acid

Question 10

What are phospholipids?

Answer 10

Glycerol + 2 fatty acids + phosphorus

• water and fat-soluble
• emulsifier

Question 11

What are sterols?

Answer 11

• cholesterol

- non-essential nutrient