Milk

Question 1

Protein in milk (NV)

Answer 1

HBV, easily digested, caseinogen, lactalbumin, lactoglobulin

Question 2

Carbs in milk (NV)

Answer 2

Disaccharide lactose. Lactic acid in bacteria change to lactose to lactic acid when milk goes sour. Lacks fibre

Question 3

Fat in milk (NV)

Answer 3

Saturated. Present in fine emulsion. Easy to digest. Butyric acid, lecithin, cholesterol

Question 4

Minerals in milk (NV)

Answer 4

Calcium, phosphorus, magnesium and potassium

Question 5

Vitamins in milk (NV)

Answer 5

Vit A, D, B1, B2, B3 (Vit C lost during processing)

Question 6

Water in milk (NV)

Answer 6

87% easy to digest

Question 7

Dietetic value of milk

Answer 7

1. Easily digested nutrients
2. Assists growth
3. Low fat diets- skimmed milk due to high cholesterol
4. Lacks fibre, starch, Vit C and iron
5. Cheap and easily available
6. Versatile

Question 8

Culinary uses

Answer 8

1. Batter (pancakes)
2. Glaze (scones)
3. Drink (milkshake)
4. Sauce (Roux)
5. Enrich (Mash potato)
6. Dessert (Custard)
7. Baking (Bread)

Question 9

Effects of heat (5)

Answer 9

1. Protein coagulates and skin forms on top
2. Slight change of flavour due to caramelisation of lactose
3. Some loss of B group vitamins and total loss of Vit C
4. Bacteria destroyed
5. Slight change of colour

Question 10

Guidelines of buying milk

Answer 10

1. Buy from retailer that has a strict hygiene policy (HACCP)
2. Check expiry date

Question 11

Guidelines of storing milk

Answer 11

1. Store in fridge at 2 degrees
2. Once opened use quickly
3. Store in its own sterile container
4. Don’t mix with other dates
5. Use in rotation
6. Don’t expose to sunlight

Question 12

Steps to Homogenised milk

Answer 12

Heated to 60 degrees.
Forced through tiny holes at high pressure to break up fat.
Fat spread through milk.
Causes smoother and creamier taste.

Question 13

Pasteurisation of milk

Answer 13

Heated to 72 degrees for 25 seconds then cooled quickly to 10 degrees.
All pathogenic bacteria killed,
Some souring bacteria killer (keeps better).
Loss of Vit C and some Vit B.

Question 14

Ultra heat treatment of milk

Answer 14

Long life milk.
Heated to 132 degrees for 1 second.
Cooled quickly and sealed in sterile container.
Kills all microorganisms.
Keeps milk for several months when unopened.
Destroys Vit C and B.
Change of flavour.

Question 15

Evaporation of milk

Answer 15

Pasteurised, evaporated to 1/2 its volume, homogenised.
Sealed in tins and heat treated to 115 degrees for 20 mins.
Long shelf life.
Vit C and B lost.
Flavour and colour change.
Bacteria destroyed.

Question 16

Condensed milk

Answer 16

Pasteurised, evaporated to 1/3 its volume, homogenised.
15% sugar added.
Cooled and sealed in tins, heated to 115 degreese for 20 mins.
Long shelf life.
Vit C and B lost.
Flavour and colour change.
Bacteria destroyed.

Question 17

Dehydrated milk

Answer 17

Homogenised, evaporated to 60%, then spray/roller dried.
Handy in emergencies, reconstituted with water.
Flavour change, bacteria destroyed etc.

Question 18

Roller drying

Answer 18

Milk poured over heated revolving drum.
As milk comes into contact with hit drum moisture evaporates and powder sticks to drum. Dry milk scrapped off.
Cooled and packed into airtight containers.
Has a cooked taste, slightly lumpy and does not reconstitute easily

Question 19

Spray drying

Answer 19

Milk lightly sprayed into hot air chamber.
As falls moisture evaporates off leaving fine powder.
Cooled and packaged.
More expensive but reconsistues easily and smoother

Question 20

Safety of milk

Answer 20

Milk is ideal for bacteria to grow.
Controls inspection and testing of herds for diseases. (HSE)
Registration of all farms and dairies must follow strict guidelines.
Sampling of raw milk for antibiotics residue or bacteria.
Pasteurisation of milk.

Question 21

Classification of milk

Answer 21

1. Flavoured (chocolate)
2. Whole (4% fat)
3. Low fat (1.5% fat)
4. Skimmed (0.1% fat)
5. Fortified
6. Soya/oat/coconut
7. Buttermilk