Beef farming systems

Question 1

What factors effect meat quality?

Answer 1

• Production
• Transportation pre-slaughter
• Immediate pre-slaughter conditions
• Meat storage
• Preparation
• Cooking

Question 2

What determines time of slaughter?

Answer 2

• System
• Birth date
• Age
• Feed type
• Breed

Question 3

How does cattle vary?

Answer 3

• Genetics
• Nutrition
• Cow efficiency
• Management

Question 4

Labelling

Answer 4

Maximum fat and connective tissue is allowed but excess must be labelled

Question 5

Nutrition of meat

Answer 5

• 62-76% water
• 16-22% protein
• 2-4% lipid
• 0.6-2.7mg iron

Question 6

Lipid content of meat

Answer 6

• Intermuscular
• Specialised cells
• Unique flavours

Question 7

What are the 2 tertiary structures of protein?

Answer 7

Fibrous and globular

Question 8

Fibrous protein

Answer 8

• Rod shaped
• Twisted polypeptides
• Structural proteins (collagen, keratin, elastin)

Question 9

Globular protein

Answer 9

• Spherical
• Folding polypeptides
• Non-polar core (myoglobin, enzymes, actin)

Question 10

What are the 3 sub-groups of meat proteins?

Answer 10

Contractile, structural and sarcoplasmic

Question 11

Myoglobin

Answer 11

• Iron containing protein
• Dictates meat colour
• Can be denatured

Question 12

Connective tissue

Answer 12

• Surrounds muscles
• Provides stability
• Effects tenderness
• Example is collagen

Question 13

Collagen

Answer 13

• Mechanical strength
• Forms gelatine

Question 14

What is the sarcomere?

Answer 14

Smallest contractile unit of the cell made from insoluble proteins

Question 15

What is rigor mortis?

Answer 15

No ATP production after slaughter causing a muscle lock and rough texture

Question 16

What changes the rate of rigor mortis?

Answer 16

• Glycogen store
• Metabolism of animal
• Muscle temperature
• Fat layers (insulation)
• Muscle location
• Environment temperature

Question 17

pH reduction post-slaughter

Answer 17

From 7.2 to 5.5 which effects water holding capacity as highest point is 5.3-5.7 pH

Question 18

How does pH reduction vary?

Answer 18

• Temperature
• Glycogen levels

Question 19

How is meat effected by rigor mortis and pH?

Answer 19

PSE (pale, soft, exudative) or DFD (dry, firm, dark)

Question 20

When does PSE occur?

Answer 20

• Rapid drop in pH
• Rapid animal metabolism
• High temperature
• Denatured proteins
• High drip loss

Question 21

When does DFD occur?

Answer 21

• Rigor mortis at high temperature
• Low glycogen store
• Microbial spoilage
• Low drip loss
• High pH

Question 22

Conditioning of meat

Answer 22

• Rigor mortis is irreversible
• Correct meat is left to age for 21 days to become tender
• Proteolysis is used to degrade proteins and loosen structure