Dairy

Question 1

how does the blood carrying nutrient get to secretory cells

Answer 1

capillaries

Question 2

within secretory cells what organelles synthesise milk components

Answer 2

Endoplasmic reticulum and ribosomes

Question 3

what can be considered as milk components

Answer 3

proteins and lipids

Question 4

in what form are the milk components moved out of the cell

Answer 4

vesicles

Question 5

what organelle facilitates the transport of milk components out of the cell

Answer 5

Golgi

Question 6

where are the vesicles deposited

Answer 6

the lumen of the alveoli

Question 7

after the lumen of the alveoli where does the milk components go

Answer 7

milk cistern

Question 8

where are the milk components stored

Answer 8

milk cistern

Question 9

what hormone stimulates muscle contraction that results in milk excretion

Answer 9

oxytocin

Question 10

where does the milk move to after muscle contraction

Answer 10

teat cistern

Question 11

percentage of water in milk

Answer 11

87%

Question 12

Percentage of fats in milk

Answer 12

2.4-5.5%

Question 13

percentage of milk solids

Answer 13

9%

Question 14

what is meant by the term milk solids

Answer 14

vitamins, minerals, proteins, carbohydrates and enzymes

Question 15

how do milk fats exist and how are they stabilised

Answer 15

in fat globules

by a membrane

Question 16

what gives the milk a yellowish tinge

Answer 16

Beta-carotene

Question 17

triglyceride to fatty acid/sterols/phospholipids composition of milk fats

Answer 17

98% to 2%

Question 18

fats in milk are a major source of and

Answer 18

energy and nutrients

Question 19

what three things causes milk to go rancid when exposed to them

Answer 19

lipases, light and oxygen

Question 20

protein composition of milk

Answer 20

18% Whey
80% casein
2% other

Question 21

what enzyme breaks down lactose

Answer 21

beta-galactosidase

Question 22

what are the fat-soluble vitamins found in milk

Answer 22

A
D
E
K

Question 23

What are the water-soluble vitamins found in milk

Answer 23

B

C

Question 24

4 reasons to process milk

Answer 24

safety
preservation
variety
economic or convience

Question 25

reasons why milk has high spoilage

Answer 25

water activity nutrition value source

Question 26

four spoilage enzymes of milk

Answer 26

lipases phospholipases proteinases lactase

Question 27

what do lipases in milk do?

Answer 27

hydrolyses the fats causing rancidity

Question 28

What do proteinases in milk do?

Answer 28

hydrolyses proteins giving age gelation (lumps) and off-flavours

Question 29

What does lactase do?

Answer 29

turns lactose into lactic acid

Question 30

what do phospholipases do

Answer 30

break down milk fat globule causing creaming

Question 31

the temperature required for LTLT(low temp, long time) processing

Answer 31

63 degree

Question 32

the temperature required for HTST(high temp, short time)

Answer 32

72 degrees

Question 33

the temperature required for HHST(higher heat, short time)

Answer 33

100

Question 34

the temperature required for UHT

Answer 34

138-150

Question 35

what enzyme is used to test the sufficiency of pasteurisation

Answer 35

alkaline phosphatase

Question 36

Why is alkaline phosphatase used

Answer 36

>heat stability than milk pathogens

Question 37

3 alternatives to pastuerisations

Answer 37

ultraviolet light, high-pressure processing and pulsed electric fields

Question 38

why must milk be pasteurised before homogenisation

Answer 38

to inactivate lipases to stop rancidity

Question 39

what does homogenisation do to milk?

Answer 39

reduces fat globule size | prevents separation

Question 40

what is the isoelectric point signify

Answer 40

the point at which a protein is least soluble

Question 41

how does adding acid coagulate milk

Answer 41

changes the pH to the isoelectric point of the wanted protein

Question 42

how does adding salt coagulates milk

Answer 42

when added in excess the salts aggregate together drawing water away from the protein and it ppts

Question 43

how does chymosin coagulate milk

Answer 43

chymosin enzyme cuts off the negatively charged K-casein micelle tails reducing the repulsion like charges and allowing them to coagulate