Final: Baking Apps (Flours & Leaveners)

Question 1

Flours: Understand what the milling process of flour is

Answer 1

Flour – typically refers to wheat flour
Other grains can be used – will be indicated in the name (ie rice flour)
Milling - grinding and refining of cereal grains,
can select some portion or all of grain in final product called flour.

Question 2

Flours: Understand what steps are involved in the milling process

Answer 2

Steps include:
1. Tempering grain - steam to help remove bran
2. Grinding - splits grains, breaks into component parts
and then breaks up component parts
3. Extraction (Sifting) - air classification system to separate out component parts

Question 3

Flours: Know the protein components of flours

Answer 3

Wheat flours - proteins
Soluble proteins - albumins and globulins
Contribute to the structure of baked products
Gluten proteins - glutenins and gliadins
Enzymes – α-amylase, B-amylase, Lipase, lipoxidase

Proteins in wheat flour – Functional roles
Albumins contribute to structure of baked products
Enzymes - alter character of flour as catalyze chemical
reactions:
α-amylase cleaves maltose units from starch
molecules
β-amylase can produce dextrins
lipases in germ: hydrolytic rancidity
lipoxidase: oxidative rancidity
Gluten – structure and elasticity in baked products and breads

Question 4

Flours: Know what self-rising flour is

Answer 4

Self-rising flour - flour to which baking powder and salt have been added, semi-mix (equiv.. to 1.5 tsp baking powder + 1⁄2 tsp salt/cup flour)
good for biscuits

Question 5

Flours: Know the enrichment nutrients included in flour.

Answer 5

Adds back some nutrients that are lost
• Thiamin, riboflavin, niacin, folic acid, and iron
Important nutritionally, no effect on baking properties

Question 6

Flours: Understand the gluten complex – know what protein components make up the gluten complex, how it is made and affected in recipes

Answer 6

Made up of gliadin & glutenin in equal amounts gliadin
- sticky & fluid, elliptical single polypeptide
chains
• 36,500 mw
• compact, held in shape by internal disulfide bonds
• has glutamine (imp. in intermolecular H bonding) &
proline (restricts protein shape)
• pIatpH6.5
glutenin - very elastic, fibrous & elongated shape • up to 15 million mw
• disulfide bonding between polypeptide subunits
• has intramolecular disulfide bonding too
• pI at pH5.2 - 5.6
• less soluble than gliadin

Question 7

Flours: Understand the concept of staling and ways

Answer 7

Retrogradation of amylose molecules released from starch granules during gelatinization first as bread cools, then continued retrogradation within starch granules over the next few days due to folding of branches of amylopectin (can be reversed if bread heated but recurs when warmed bread cools)
Moisture leaves starch molecules and returns to gluten which can now toughen especially at crust (surface of bread)
—
Refrigeration temperatures (4 - 8 C)
result in most retrogradation (most rapid) due to concentration effects which promote the process
Room temperature storage
result in slower retrogradation rates but problems with molding
Freezing conditions
inhibit retrogradation of bread

Question 8

Leaveners: Know the types of leaveners used in baking

Answer 8

1. BAKING SODA:
   Bicarbonate of Soda
   Used along with another acidic ingredient to produce carbon dioxide
   ie liquids such as buttermilk, sour cream, yogurt, sour milk, fruit juices
   Or other acidic ingredients in the batter – brown sugar, honey, molasses, cream of tartar
   Reaction occurs quickly – necessitates mixing and baking quickly after
   Baking soda must be dissolved before it can react with the acids
   Without sufficient acid to react with the baking soda, product will have:
   a “soapy” flavor (NaCO3)
   yellowish tint (if light colored)
   and may have lower volume
2. Baking powder (single and double acting)
   -Single Acting – contains one acid salt in addition to baking soda and cornstarch
   -Double Acting – contains 2 acid salts in addition to baking soda and cornstarch – one reacts in cold conditions, the other in hot conditions
3. Baking Ammonia
   (NH4)2CO3
   Produces Ammonia, CO2 and H2O when moist and heating
   Leaves aftertaste so can only be used in small quantities
   Ideal for doughs that require only a little leavening (biscotti, springerle, and lebkuchen)
   May be used in doughs that are not mixed right away

Question 9

Leaveners: Know the difference between chemical leaveners

Answer 9

Leaveners – air, steam, and chemical leaveners (usually baking powder; some soda may be added to neutralize an acidic dough)
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Baking soda
Baking powder (single and double acting)
Baking ammonia

Question 10

composition

Answer 10

Consists of:
 protein (8-12%)
 fat (about 2%)
 water (12 - 15%)
 remainder is carbohydrate (at least 70%).