Dairy and Eggs 2

Question 1

Milk fat percentages

Answer 1

Whole milk = 3.5% fat

Low-fat milk = 1-2% fat

Skim milk = .1-.5% fat

Question 2

Types of creams

Answer 2

Spreading creams:
Plastic cream 65-85% fat
Clotted cream = cream skimmed from long-heated milk, 55%+ fat
Double cream = dense cream skimmed from surface of separate milk, 48% fat

Whipping cream:
Heavy whipping cream 38% fat, whipping cream 35%
Crème fraiche 30-40% fat

Pouring, coffee creams:
Light whipping cream 30-36% fat
Light cream 20% fat, coffee cream 25%
Half-and-half: 12% fat

Question 3

What is cooking cream?

Answer 3

AKA culinary cream

Stabilized with emulsifiers and enzymes for heat stability (no curdling or breaking)
- ideal for simmering in a dish or bringing to boil

35% fat

Question 4

Types of butter

Answer 4

Raw cream butter (10 day shelf life)

Sweet cream butter 80% fat (+/- 1-2% salt)

Cultured cream - fermented, sour

European style butter at least 81% fat (pastries)

Whipped butter - sweet cream butter injected with N gas

Beurre cuisinier, beurre patissier, beurre concentrer - nearly 100% butterfat

Ghee - clarified butter, lactose and proteins removed

Question 5

Transfats found in

Hydrogenation equation

Adverse health effects

New process to replace hydrogenation

Answer 5

Small amounts in beef, butter but 75% are from hydrogenation

Hydrogenation: H2 + Ni + unsaturated FA –> saturated FA

Adverse affects on blood lipids increasing CVD
2015 not GRAS
2018 banned in Canada

Interesterification process used instead
- rearrangement of FA on glycerol within TAG
- requires emulsifier use
- uses palm oil (plantation environmental concerns)

Question 6

Fermented milks

Answer 6

North America: yogurt (turkish word), buttermilk, crème fraiche, sour cream

Scandinavia: villi, ropy milks

Central asia: koumiss (alcoholic), kefir

Question 7

How to make yogurt

Answer 7

1) heating milk to concentrate protein and denaturing lactoglobulin for firmer texture

2) cool and ferment:
- 40-45°C for 2-3 hours - thick protein network, whey leakage
or
- 30° for 18 hours - fine network, more whey

Question 8

Crème fraiche, sour cream and buttermilk descriptions

Answer 8

Crème fraiche: thick, tart, buttery, high fat low protein, can be cooked

Sour cream: leaner, firmer and higher protein than crème fraiche, added to soups and stews

Buttermilk: low fat portion of milk after churning (true)
- in stores: skim milk fermented until acidic and thick

Question 9

Benefits of probiotics

Answer 9

Beneficial live organisms which can improve gut microbiome and improve health

They can make lactase

Improved immune system

Improves IBS

Reduces anti-biotic caused diarrhea

Question 11

Characteristics which effect cheese

Cheese microbes

Answer 11

Concentration from milk: 5 - 10x:
1) Species of animal
2) Breed of animal
3) Feed and seasons
4) Pasteurized or raw milk (allowed in Canada if method used can eliminate pathogens)

1) Starter bacteria: found in milk, acidify it
- mesophilic - moderate temp loving
- thermophilic - high temp loving
2) Proprionibacteria: make holes in swiss cheese
3) Smear bacteria: applied to rind, strong smelling
4) Molds (ex. Penicillium spp.) on rinds and veins
- dryer conditions

Question 12

Cheesemaking process

Answer 12

Acid for fine, fragile curds OR
Rennet (veg or from 1st cow stomach) for robust, rubbery curds –> Casein clumps

Drain, shape, salt
Salting: draw moisture out, firm protein structure, slow microbial growth, alters ripening enzyme activity
- temp and humidity controlled by Affineur (cheese ripener in France)

Question 13

Classifications of cheese based on moisture content

Rind types

Answer 13

Fresh = >80% moisture, ricotta
Soft = 67-80% moisture, brie or camembert
Semi-soft = 62-67% moisture, havarti or munster
- veined stilton or roquefort
Firm = 50-62% moisture, gouda or cheddar or gruyere
Hard = <50% moisture, parmesan

Bloomy (mold sprayed on soft cheeses), washed (reddish, soft, semi-soft and firm), brushed (semisoft or firm) or natural (semisoft or firm)

Question 14

Properties affecting cooking with cheese

Answer 14

Aged cheese blisters with big blisters, unaged small
- choose cheeses that resist oiling off

Stretchability depends on Ca Phosphate content - less Ca more stretch

More moisture and fat —> more meltable

Question 15

Egg definition SFCR

Answer 15

egg of domestic chicken or turkey egg, no balut (fertilized egg)

Scientific: organic vessel where embryo develops, females lay as a means of reproduction

Question 16

Anatomy of an egg

Answer 16

Bumpy, CaCO3 shell, 17000 pores, semipermeable
- Thin cuticle outside called Bloom

Air cell: forms from cool and contraction after laying, between inner and outer membrane
- grows as egg ages (old eggs float)

Egg white: albumin is 2/3 weight of egg, 88% water
- 40 proteins (11% of white weight)
- trace micelles and vitamins, mostly ovalbumin (54%), globulins (8%) and avidin (.05%)

Yolk: 1/3 of weight, water (49%), protein (17%), fat (30%)
- source of lecithin - good emulsifier
- fat is 70% unsaturated, 30% saturated
- Vitamins A, D, E, B1, B2, B12 and calcium

Chalzae: opaque white ropes holding egg yolk in center of egg from yolk casing to shell
- more chalzae - fresher egg

Question 17

Egg grading

Regular egg weights

Answer 17

Canada A (retail): no abnormalities, no more than 3 spots, regular shape

Canada B (ingredients/liquid eggs): min. 49g, slightly oblong yolk, slightly abnormal shape, no cracks

Canada C (as ingredient/liquid): under 49g, oblong yolk, blood spots, cracked

Canada Nest Run: not graded

Small = 42g, medium = 49g, large = 56g, X large = 63g, jumbo = 70g

Question 18

Brown vs. white eggs

Answer 18

Brown laid by Rhode Island hens, white laid by Longhorn hens

Question 19

Nutrients in eggs

Answer 19

9 EAA - high bioavailability, especially egg white

Iron, vitamins A, D, and E, B12, choline, lutein and zeaxanthin

Question 20

Egg storage

Answer 20

Washing eggs for salmonella prevention removes natural protective layer
- takes 4 days in fridge to deteriorate and 1 day on counter

Freezing eggs: whites in air tight container, yolks or whole eggs blended mixed with sugar/salt/acid to prevent thickening

Question 21

Egg as emulsifier

Answer 21

Any part of egg can be used for permanent emulsification but lecithin is only in the yolk

Salt and sugar increase emulsifying effect

Decreasing emulsifying effects: freezing, freeze-thaw, high temp, acid or sat

4:4:1 ratio oil, egg, vinegar

Question 22

Binding properties of egg

Foaming properties of egg

What increases/decreases foaming

Answer 22

high protein makes for good binder (protein coagulation during cooking)
- can be adhesive for batter, meatloaf, structure strength
- too much egg makes for firm and dry

Can foam 6-8x volume to aerate products due to protein + water content in egg white especially
- entrapment of air by beating albumin denatures and reveals hydrophobic/hydrophilic portions which align and trap air bubbles

Increasing foaming: freshness of egg, flour/sugar, cream of tartar (lowers pH), copper/stainless steel/glass bowls

Decreasing foam: quality of egg protein, salt, cold, fat, older egg (loss of water)