Seminar 2 – Starch & Grain Components
Brook Benton, MS, RD, LDN, CDE
Nanna Cross, PhD, RD, LDN
Review of Lab 1
Questions regarding Unit 2 lab reports?
A. Starch principles
 Pages 23-24 in Laboratory Manual
 Follow instructions for the type and amount of starch in
Table 3.1, page 24.
 Do ONLY treatment numbers 1, 3, 5, 7 & 8 and describe
firmness and appearance in the table.
 Answer questions 1-5, page 24
B. Effect of water temperature on starch dispersion
 Page 25; answer questions, page 25
Starch
 Storage form of carbohydrate
 Common sources
 Seeds, roots, tubers
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Cereal grains – corn, wheat, rice, oats
Legumes
Roots and tubers – potato, tapioca, arrowroot
Starch
• Less common sources of starch
• Check out Web Resources within the course
• www.quinoa.net
• www.grains.org
• www.ilovepasta.org
• www.riceland.com
Starch Molecule
 Starch is a polysaccharide.
 Polysaccharide is made up of hundreds or thousands
of glucose molecules.
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Polysaccharide – a complex carbohydrate.
Glucose – a monosaccharide or simple sugar.
Two Kinds of Starch Molecules
 Amylose
 Long chainlike
 Corn starch and wheat flour
 Amylopectin
 Branched, bushy structure
 Tapioca has the highest amount of amylopectin
 Most starches are a mixture of the two of these in varying
degrees
Two Kinds of Starch Molecules
 Amylose
 Provides gelling characteristic
 For example, pudding or cream pie
 Amylopectin
 Provides cohesion or thickening properties when cooked with
liquid
 For example, gravy or thickening for fruit pies
Changes in Starch with Cooking
 Moisture – dissolves starch
 Heat – starch granules swell
 Cooling - retrogradation
Preventing Lumping in
Powdery Starches
 Before hot liquids are combined with starch, the particles of starch
must be separated to bring about a uniform dispersion of well
hydrated starch granules
 This process can be accomplished in one of three ways before
adding hot liquid:
 Dispersing the dry starch with melted fat
 Blending the dry starch with sugar
 Mixing the dry starch with cold water to form a slurry
Characteristics of Native Starches
Native Starches
Characteristics
 Cornstarch
 Clear glossy sauce
 Tapioca
 Tolerates freezing/thawing
 Wheat flour
 Opaque sauce
 Potato
 Doesn’t tolerate heat
 Sweet rice
 Tolerates freezing/thawing
 Arrowroot
 Clear glossy sauce; tolerates
high heat and acid
*Table 13-2. page 219,
Introductory Foods.
Starch Hydrolysis
 Breakdown of starch molecule produces glucose
 Amylase
Enzyme that hydrolyzes starch
 Acid
 May be a catalyst in reaction

Factors that alter gelatinization and
gelation
How do each of these factors influence gelatinization
or gel formation of starches?
1. Heat?
2. Agitation?
3. Other ingredients?
Acid?
2. Sugar?
1.
Cereal Grains
 Cereal grains are seeds of the grass family.
 Most important cereals used for food:
 Wheat, corn (maize), rice, oats, rye, barley, millet
 Cereal refers to a large group of foods made from
grains:
 Flours, meals, breads, alimentary pastes or pasta
Structure of Whole Grains
 Outer bran - high in fiber
 Germ - rich in fat and
protein
 Starchy endosperm -
milled white flour comes
entirely from the
endosperm
Nutritive Value of Cereal Products
 Varies depending on the part of the grain that is used
and the method of processing.
 Enriched flour is white flour with specified B vitamins
and iron added.
Cereal Cookery
 Main purpose: to improve palatability and digestibility
 Factors that affect time required to cook include:
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Size of cereal particle
Amount of water used
Presence of absence of bran
Temperature
Method of cooking used
Cooking Methods
 Granular Cereals
 4 to 5 cups of water to 1 cup of cereal
 Rolled Oats
 2 to 2 ½ cups of water to 1 cup of cereal
 Rice
 Twice the volume in water
 Brown rice takes twice as look to cook as white rice
 Pasta
 2 – 3 quarts of boiling water for each 8 ounces of pasta
 Increases to 2 – 2 ½ times its original volume after cooked
Name That Starch or
Grain Term!
Name That Starch or
Grain Term!
I am the building block of a starch –
also known as a monosaccharide
Name That Starch or
Grain Term!
I am the starch that has the highest
amount of amylopectin – I provide the
most thickening properties
Name That Starch or
Grain Term!
I am the sum of changes that occur in the first stages
of heating starch granules in a moist environment
- this includes swelling of granules as water is
absorbed and disruption of the organized granule
structure
Name That Starch or
Grain Term!
I am the process which takes place on the cooling of
the starch paste following gelatinization
Name That Starch or
Grain Term!
I am a mixture of fat & flour cooked
together
Name That Starch or
Grain Term!
Grits are made from me
Name That Starch or
Grain Term!
I am a basic dish produced when a cereal
grain is browned in a small amount of hot
fat before cooking it in water
Name That Starch or
Grain Term!
I am produced by crossbreeding rye
and wheat
Name That Starch or
Grain Term!
When a starch has been _________, instant
cereals can be prepared very quickly,
simply by adding hot water