1. NS415 Food Science with Lab
Seminar 2 – Starch & Grain Components
Brook Benton, MS, RD, LDN, CDE
Nanna Cross, PhD, RD, LDN

2. Review of Lab 1

3. Questions regarding Unit 2 lab reports?
A. Starch principles
Pages 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

4. What are the most common sources of food starch?

5. Starch Storage form of carbohydrate Common sources
Seeds, roots, tubers
Cereal grains – corn, wheat, rice, oats
Legumes
Roots and tubers – potato, tapioca, arrowroot

6. Starch Less common sources of starch
Check out Web Resources within the course

7. Starch Molecule Starch is a polysaccharide.
Polysaccharide is made up of hundreds or thousands of glucose molecules.
Polysaccharide – a complex carbohydrate.
Glucose – a monosaccharide or simple sugar.

8. There are two kinds of starch molecules
There are two kinds of starch molecules. What are the two kinds of starch and how do they differ in structure?

9. 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

10. 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

11. Cooking with Starches

12. What factors are required for gelatinization & gel formation of starch?

13. Changes in Starch with Cooking
Moisture – dissolves starch
Heat – starch granules swell
Cooling - retrogradation

14. 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

15. Characteristics of Native Starches
Cornstarch
Tapioca
Wheat flour
Potato
Sweet rice
Arrowroot
*Table page 219, Introductory Foods.
Clear glossy sauce
Tolerates freezing/thawing
Opaque sauce
Doesn’t tolerate heat
Clear glossy sauce; tolerates high heat and acid

16. Starch Hydrolysis

17. Starch Hydrolysis Breakdown of starch molecule produces glucose
Amylase
Enzyme that hydrolyzes starch
Acid
May be a catalyst in reaction

18. Factors that alter gelatinization and gelation
How do each of these factors influence gelatinization or gel formation of starches?
Heat?
Agitation?
Other ingredients?
Acid?
2. Sugar?

19. QUESTIONS???

20. What are the most important cereal grains used for food?

21. 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

22. 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

23. 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.

24. What are the main purposes of cooking cereals?

25. Cereal Cookery Main purpose: to improve palatability and digestibility
Factors that affect time required to cook include:
Size of cereal particle
Amount of water used
Presence of absence of bran
Temperature
Method of cooking used

26. What is the appropriate method for cooking the following cereals: -Granular cereals such as farina and cornmeal -Rolled oats -Rice -Macaroni or spaghetti

27. Cooking Methods Granular Cereals Rolled Oats Rice Pasta
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

28. QUESTIONS???

29. Name That Starch or Grain Term!
Let's Play a Game!
Name That Starch or Grain Term!

30. Name That Starch or Grain Term!
I am the building block of a starch – also known as a monosaccharide

31. Name That Starch or Grain Term!
I am the starch that has the highest amount of amylopectin – I provide the most thickening properties

32. 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

33. Name That Starch or Grain Term!
I am the process which takes place on the cooling of the starch paste following gelatinization

34. Name That Starch or Grain Term!
I am a mixture of fat & flour cooked together

35. Name That Starch or Grain Term!
Grits are made from me

36. 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

37. Name That Starch or Grain Term!
I am produced by crossbreeding rye and wheat

38. Name That Starch or Grain Term!
When a starch has been _________, instant cereals can be prepared very quickly, simply by adding hot water

39. The End!