Milk: Composition and Processing

Question 1

Fluid products

Answer 1

Table milk, cream (26.7hL)

Question 2

Derived (industrial products)

Answer 2

Cheese, yogurt, butter, ice cream, etc. (67.95hL)

Question 3

Dairy industry is _________________

Answer 3

Supply managed

Question 4

Consumption of dairy products

Answer 4

16.2 billion CAN$ in 2021 (11.6% of Canadian food/beverage sector)

Question 5

3 largest dairy processors in Canada

Answer 5

Saputo, Agropur, Parmalat

Question 6

By how much has milk production increased?

Answer 6

73.0M - 92.3M hL

Question 7

Where are most dairy farms and processors found in Canada?

Answer 7

Ontario and Quebec

Question 8

Main exporters of dairy

Answer 8

European Union, New Zealand, and US

Question 9

Main Importers

Answer 9

European Union, Asian countries, and US

Question 10

When the product is labelled milk ( or whole milk), it must fit into these categories

Answer 10

• must be obtained from the mammary gland of the cow
• shall contain added vitamin D that is not less than 300 international units and not more than 400 international units

Question 11

5 major nutrition groups (milk must must contain all of these)

Answer 11

Carbohydrates, proteins, fatty acids, minerals, vitamins

Question 12

Most common dairy cow breed in Canada

Answer 12

Holstein

Question 13

Milk composition

Answer 13

Water, 87%; lactose, 4,9%; fat, 3.5-3.7%; proteins, 3.6%; ash, 0,7%

Question 14

What is the most variable component in milk?

Answer 14

fat

Question 15

Lactose (milk sugar)

Answer 15

the major carbohydrate and is a energy source for young animals (also affects physical and chemical properties in milk)

Question 16

Fat (in milk)

Answer 16

present in milk in form of membrane enveloped globules

Question 17

_________ is an important component of the globular membrane

Answer 17

cholesterol

Question 18

Fat-soluble vitamins found in milk

Answer 18

A, D, E, K

Question 19

What factors affect fat content of milk?

Answer 19

breed, individual animal, stage of lactation, milking frequency, season, feed, health of cow

Question 20

Fat content function in foods

Answer 20

Lubrication (mouth feel), flavour, a reservoir of other flavour compounds, shortening effect, energy provider, nutrients

Question 21

What kind of emulsion is milk?

Answer 21

Oil-in-water emulsion

Question 22

2 types of protein

Answer 22

Particulate (casein) and soluble (serum, whey)

Question 23

Casein protein

Answer 23

Heat stable and in the form of micelles

Question 24

Whey/serum proteins

Answer 24

Easily denatured by heat and are the enzymes, antibodies, etc of milk

Question 25

Ash

Answer 25

Minerals such as K, Na, Ca, Mg, P

Question 26

Fat soluble vitamins

Answer 26

A, D, E, and K

Question 27

Water soluble vitamins

Answer 27

B and C

Question 28

How are vitamins lost?

Answer 28

Through fat seperation

Question 29

Fluid milk

Answer 29

40% of production in Canada

Question 30

Industrial Milk

Answer 30

60% of production

Question 31

Table milk

Answer 31

Milk commonly found in households (skim or homo)

Question 32

Creams

Answer 32

Elevated fat content relative to whole milk

Question 33

UHT Products

Answer 33

Shelf-stable without refrigeration (sterilized)

Question 34

Steps to processing milk

Answer 34

Clarified, standardized, vitaminized, homogenized, pasteurized, packaged, and stored

Question 35

Clarification

Answer 35

Milk is centrifuged to remove particulate matter (dirt)

Question 36

Standardization

Answer 36

Adjustment of fat content by removing some or all of butterfat by centrifugation

Question 37

Vitaminization

Answer 37

Addition of vitamin A and D

Question 38

Homogenization

Answer 38

Relatively large butterfat globules are disintegrated by shearing and impact

Question 39

Pasteurization (most important process)

Answer 39

Heat treatment to destory pathogens and extend shelf life

Question 40

3 types of pasturization

Answer 40

LT, HTST, UHT

Question 41

LT pasteurization

Answer 41

63 degrees celsius, 30min

Question 42

HTST pasteurization

Answer 42

72 degrees celsius, 16sec

Question 43

UHT pasteurization

Answer 43

140 degrees celsius, 5 sec

Question 44

Target microorganism in pasteurization

Answer 44

Coxiella burnetii

Question 45

Cooling

Answer 45

to storage temperatures

Question 46

Packaging

Answer 46

Poured into cartoons, polyethylene film, or bottles

Question 47

Storage

Answer 47

Kept at less than 4.5 degrees celsius

Question 48

Cultured products

Answer 48

Products like yogurt, sour cream, buttermilk, cottage cheese, etc created by bacteria converting lactose to lactic acid

Question 49

Important enzyme to make cheese

Answer 49

Rennin (chymosin) enzyme that causes precipitation of casein (curds)

Question 50

What part is drained away in cheese making?

Answer 50

the whey

Question 51

Evaporated and condensed milk

Answer 51

Around 50% of water is removed by vacuum evaporation

Question 52

Butter

Answer 52

Produced by churning to transform oil-in-water emulsion into water-in-oil emulsion

Question 53

Process for clustering and clumping when making butter

Answer 53

- Flocculation - Partial coalescence - Coalescence