Lab 8 : Milk Products, Fermented Milk Products, Pro-biotics and Energy-dense Applications.

Question 1

What does UHT stand for?

Answer 1

Ultra-high Pasteurized (milk)

Question 2

How is UHT milk treated?

Answer 2

-Subjected to high heat
-Packaged in aseptic container
(contains no bacteria)

Question 3

What reaction for Lactase catalyze?

Answer 3

Lactose to glucose and galactose

Question 4

Who is intended to drink lactose-reduced milk?

Answer 4

people with lactase deficiency

Question 5

What gives evaporated milk it’s color and taste?

Answer 5

Mailard reaction

slight caramel taste

Question 6

What maintains the viscosity of evaporated milk?

Answer 6

Stabilizers and preservatives

Question 7

How was buttermilk traditionally made?

Answer 7

by-product of butter-making

Question 8

How is buttermilk made today?

Answer 8

By adding bacteria culture to low/non- fat milk

transforms lactose to lactic acid = sour taste

Question 9

What can buttermilk be placed with in a recipe?

Answer 9

By adding vinegar or lemon juice to normal milk (10ml:250ml)

Question 10

Why would Acidophilus milk be consumed?

Answer 10

To help replenish the GI with Lactobacillus Acidophilus.

After antibiotic treatment

Question 11

What bacteria does Acidophilus milk contain?

Answer 11

Lactobacillus Acidophilus.

Question 12

How is sour cream made?

Answer 12

Pasteurized milk - soured by Streptococcus Lactis

which produces lactic acid

Question 13

Can sour cream be home made?

Answer 13

Yes, by combining 30ml buttermilk and 500ml fresh cream and letting it sit at room temp for 24 hrs.

Question 14

What bacteria is used to make yogurt?

Answer 14

Lactobacillus Bulgaricus
and
Streptococcus Thermophilus

Question 15

Why is Gelatin added to yogurt?

Answer 15

used as stabilizer / solidifier

Question 16

What is the function of Pectin when added to yogurt?

Answer 16

used as stabilizer / solidifier

Question 17

Why is carrageen added to yogurt?

Answer 17

used as stabilizer / solidifier

Question 18

Why are stabilizers added to yogurt?

Answer 18

To prevent the whey (yellowish liquid) from separating from commercial yogurt.

Question 19

What is Kefir?

Answer 19

A fermented milk product similar to yogurt.

Question 20

What makes kefir different?

Answer 20

Also fermented with yeast.

Question 21

What is the texture of Kefir?

Answer 21

Frizzy, frothy, piquante, bitter drink

Question 22

Where is Kefir traditionally used in dishes?

Answer 22

Russia, Eastern Europe, Middle East.

Question 23

How is cheese made?

Answer 23

Milk products coagulated/curdled.

Then separated from Whey.

Question 24

Does cheese keep the nutrients found in milk?

Answer 24

Yes, highly concentrated form of milk.

Rich in nutrient.

Question 25

What nutrients are found in cheese?

Answer 25

Protein, Calcium, Riboflavin, Vitamin A, Sodium

Question 26

What influences the flavor, body and texture of cheese?

Answer 26

``` Type of milk used Bacteria species Quantity of salt /seasoning /colours Processing method Mold used (during inoculation) Environment during ripening (temp, humidity...) ```

Question 27

Two classes of cheeses.

Answer 27

Ripened | Unripened

Question 28

Which classification of cheese has a more moisture content?

Answer 28

Unripened

Question 29

What are examples of unripened cheeses?

Answer 29

Cottage cheese | Ricotta

Question 30

What type of curds does unripened cheese have?

Answer 30

Soft and fragile

Question 31

How are soft cheeses usually made?

Answer 31

Coagulation by acid

Question 32

Which classification of cheese has a lower moisture content?

Answer 32

Ripened cheese

Question 33

What type of curds does ripened cheese have?

Answer 33

Touch and rubbery

Question 34

How are ripened cheeses made?

Answer 34

Coagulated by action of enzyme (Rennin)

Question 35

How long are cheese left to ripen?

Answer 35

3 months to 2 years

Question 36

How quickly much unripened cheeses be eaten?

Answer 36

Within a few weeks

Question 37

What is added to milk, to ripen cheeses?

Answer 37

Enzymes, Bacteria, Molds or Yeasts

Question 38

What happens to casein during ripening?

Answer 38

Hydrolysed to amino acids & ammonia.

Question 39

What happens to the fats during ripening?

Answer 39

To fatty acids and acetate

Question 40

What happens to lactose during ripening?

Answer 40

Turned to lactic acid

Question 41

What is condensed milk?

Answer 41

Evaporated milk with sugar and stabilizers added?

Question 42

Is condensed milk just as nutritious as evaporated milk?

Answer 42

No! It tends to be higher in fat, sugar content and calories.

Question 43

What type of recipes is condensed milk used in?

Answer 43

Desserts and sweets

Question 44

What does NFDM stand for?

Answer 44

Non-fat dehydrated milk

Question 45

What type of milk is usually used for making NFDM products? and why?

Answer 45

Skim milk | Because it is less perishable

Question 46

What is whey protein powder used for?

Answer 46

Increase energy and protein content of food and beverages.

Question 47

What factors cause milk proteins to coagulate?

Answer 47

Heat Acid Enzymes

Question 48

What temp do Whey proteins begin to coagulate?

Answer 48

66 C

Question 49

What are the whey proteins present in milk?

Answer 49

Lactoglobulin and Lactalbumin

Question 50

What is contained in the skin on the surface of milk when it is heated?

Answer 50

Fats, Minerals, Coagulated Whey proteins

Question 51

What precipitates along the sides and bottom of the pan when heating?

Answer 51

Calcium Phosphate, Whey proteins

Question 52

What can be done to prevent the milk from being scorched during cooking?

Answer 52

1) Use of a double boiler | 2) Stirring it constantly

Question 53

What is milk's predominant protein?

Answer 53

Casein

Question 54

Is casein effected by cooking?

Answer 54

No

Question 55

What circumstances may cause casein to curdle?

Answer 55

A higher concentration of proteins. | ex. evaporated milk, sweetened condensed milk

Question 56

What happens to milk when a unopened can of condensed milk is boiled?

Answer 56

Casein coagulate and causes the caramelized milk to gel.

Question 57

What does heat do to unstable milk products?

Answer 57

It accelerates coagulation.

Question 58

When should sour cream be added to a hot dish?

Answer 58

Right before serving, to prevent separation.

Question 59

What is sour cream sensitive to?

Answer 59

Heat

Question 60

What is the normal pH of milk?

Answer 60

6.5 - 6.7

Question 61

What pH does casein start coagulate?

Answer 61

Below 5.2

Question 62

Why does casein in milk coagulate below a certain pH?

Answer 62

Negative charges that stabilize Calcium phosphocaseinate micelles are neutralized (by H+ from acidic environment)

Question 63

What enzyme is used for manufacturing cheese?

Answer 63

Rennin (sold as Rennet)

Question 64

What are the two steps that take place when rennet is added to milk?

Answer 64

1) Rennin cleaves kappa-casein bond (forming para-kappa casein) 2) Exposed chemical group reacts with Ca (form curds)

Question 65

How would you minimize the effects of milk curdling when combined with food?

Answer 65

1) Add acid to milk (not milk to acid) 2) Heat both before combining (acid food & milk) 3) Thicken acid/milk before combining 4) Serve combination promptly

Question 66

What do milk foams consist of?

Answer 66

Air bubbles surrounded by thin layer of protein. | Fat interspersed as a stabilizer.

Question 67

What factors effect milk/cream foams?

Answer 67

1) Viscosity (Increasing viscosity of milk = more stable foam) 2) Fat concentration (increases formation and stability) 3) Temperature (cool temp = fat droplets to harden) 4) Sugar (delays curdling)

Question 68

What happens to cheese when it overheated?

Answer 68

``` Proteins coagulate (become tough and rubbery) Fat emulsion may break (fat separates) ```

Question 69

Which type of cheese is more resistant to heat?

Answer 69

Firm cheeses

Question 70

Which type of cheese is better used for cheese sauces?

Answer 70

Ripened, sharp cheeses blend better (more flavor).

Question 71

What are characteristics of a nourishing drink?

Answer 71

High protein / High Energy | Skim milk is common base (Full cream milk for more energy)

Question 72

What can be done to reduce the amount of saturated fat in nourishing drinks?

Answer 72

Skim milk and oil.

Question 73

What does whey powder contain?

Answer 73

Complete high quality proteins

Question 74

What is yogurt cheese?

Answer 74

A low fat, creamy cheese.

Question 75

How can yogurt cheese be made?

Answer 75

At home, suspend the yogurt in cheese cloth, allowing the liquid to drip out over night.