Flour and Leavening Agents

Question 1

How is wheat classified?

Answer 1

By:

• Kernel color
• protein starch structure (hard/soft)
• planting season

Question 2

Types of Wheat

Answer 2

• hard red winter, soft red winter
• hard red spring
• soft white, hard white
• durum
• triticale

Question 3

Hard red winter wheat is made up of how much protein? How is it related to North America?

Answer 3

• 12% protein

- primary flour wheat source for N.A.

Question 4

Milled wheat will yield about what percentage of flour?

What part of the wheat produces this yield? What is remaining of the wheat that’s not milled?

Answer 4

1. 75% flour
2. Endosperm of the seed
3. Remaining: Wheat germ, bran, residual endosperm

Question 5

What is the major determinant of flour quality?

Answer 5

protein content and dough formation

Question 6

The protein complex is also known as…?

Answer 6

gluten

Question 7

What makes up gluten?

Answer 7

Two proteins: Gliadins and Glutenins (SH and S-S bonds)

Question 8

What is the consistency of Gliadins and glutenins?

Answer 8

glutenin- very elastic

gliadins- fluid and sticky

Question 9

what are the differences in density and size in gluten balls made of all-purpose, rye, and whole wheat flour?

Answer 9

size (big to small): all purp., whole wheat, rye

density (least to most): all purp., whole wheat, rye

Question 10

About how much water can bread dough contain? (percentage)

Answer 10

40% water

Question 11

what is the key to the development of structure and volume in baked products and why?

Answer 11

Key: leaving agents

- increases the volume and lightness of your baked product

Question 12

What are the three methods leavening agents can work?

Answer 12

• physical
• chemical
• biological

Question 13

what are the most common leavening agents? what does it increase and by how many times?

Answer 13

• air- volume increase- 1/273x when heated

- steam- volume of water increase- 1600x when heated

Question 14

what is the chemical equation for baking soda (1)(leavening agent)?

Answer 14

2NaHCO3 –> Na2CO3 + H2O + CO2

Question 15

what is the chemical equation for baking soda (2)(leavening agent)?

Answer 15

NaHCO3 + HX –> NaX + H2CO3

Question 16

what is the chemical equation for baking soda (3)(leavening agent)?

Answer 16

H2CO3 –>H2O + CO2

Question 17

what is the chemical equation for baking soda (4)(leavening agent)?

Answer 17

NaHCO3 + HKC4H4O6 --> NaKC4H4O6 + H2O + CO2
Tartaric acid 
COOH
|
CHOH
|
CHOH
|
COOH

Question 18

what is triticale?

Answer 18

cross b/w wheat and rye

Question 19

define shortening. What does it do to gluten? What is it used in?

Answer 19

flour mixture- tenderize by limiting length of gluten protein structure which can develop

• inhibit disulfide bridges b/w gluten & gliadin (protein)
• used in cake and pastry

Question 20

what is an important thing to consider in your choice of fat? give examples

Answer 20

plasticity- softness, spreadability of a fat
eg. butter is not plastic since its really firm and brittle when cold
liquid oil is fully plastic

Question 21

What determines the plasticity, brittleness, and spreadability of fat?

Answer 21

the fatty acid composition

Question 22

what is the fatty acid composition of butter?

Answer 22

saturated, mono and polyunsaturated fatty acids

Question 23

what is the fatty acid composition of oils (flaxseed, vegetable, etc)

Answer 23

higher polyunsaturated fatty acids

Question 24

How do we incorporate shortening into flour in order to have that shortening effect on products and tenderization of products?

Answer 24

via the introduction of multiple layers of fat to separate starch and gluten molecules

Question 25

define rendering

Answer 25

heating animal fat to stabilize it