Grains

Question 1

What is the importance of grains?

Answer 1

• Grains are very versatile - at least one type can be grown almost everywhere.
• High in carb content and are easily stored and prepared

Question 2

Describe the general structure and composition of a grain.

Answer 2

Bran - outer layer, contains most of the vitamins and minerals
Aleurone - under bran layer, high in protein and phosphorus
Endosperm - centre portion, most of the protein and starch
Germ - small shallow end, most of riboflavin content

Question 3

Identify the three properties of starch

Answer 3

• raw starch is insoluble in cold water
• cooked starch forms a paste - this differs between the type of starch (eg. corn or potato)
• texture is soft and cohesive

Question 4

Differences between amylose and amylopectin

Answer 4

amylose: linear polysaccharide, contributes to gelling
amylopectin: highly branched polysaccharide, forms thickening properties

Question 5

Discuss factors requiring control when cooking starch

Answer 5

• Heating temperature - differ between starch types
• Heating time - heated rapidly so granules swell quickly at high temps
• Stirring intensity - accelerates gelatinization
• pH of the mixture - low pH can decrease viscosity,
• Addition of other ingredients - sugar, fat and protein

Question 6

Identify five types of wheat flour

Answer 6

Cake
Pastry 
All Purpose 
Self Raising 
Strong / Bread making

Question 7

Explain the classes of wheat

Answer 7

• Hard
• Soft
• Durum

Question 8

Explain the grades of wheat flour

Answer 8

Graded based on the four streams used to make them

Patent flours divided into: 
 First patent
- Second patent 
- First clear
- Second clear 
- Red dog

Question 9

Types of flours

Answer 9

• hard wheat
• soft wheat
• wholemeal
• white

Question 10

What is enriched flour?

Answer 10

White flour with added B vitamins and iron, improves the nutritional status of people

Question 11

Properties of gluten flour

Answer 11

• comprises of two parts = glutenin & gliadin

- provides elasticity and strength

Question 12

Other non wheat flours

Answer 12

• cornmeal
• oat flour
• barley flour
• buckwheat flour
• rice flour

Question 13

What are the 3 categories of rice type?

Answer 13

• short grain
• medium grain
• long grain

Question 14

Define Value Added Agriculture?

Answer 14

Process that transforms an original raw agricultural commodities form into something new through packaging, processing, cooling/drying, extracting & other processes

Question 15

What are 3 examples of Value Added Agriculture?

Answer 15

• breakfast cereals (many are ready to serve mixtures with added sweetners)
• baked products (flour liquid, fat, sugar, salt, eggs, leavening agents and flavourings)
• corn refining (corn id converted into starch, oil, protein and fibre)

Question 16

Name four products derived from corn

Answer 16

Corn oil, feed products for animals, starches, sweetners and alcohol/ chemicals (from fermentation)

Question 17

What is the role of liquid in a baked product?

Answer 17

• hydrates the protein and starch

- helps with gluten development an dispersion of all colloids

Question 18

What is the role of fat in a baked product?

Answer 18

• facilitates air incorporation

- tenderises product

Question 19

What is the role of salt in a baked product?

Answer 19

• adds flavour

- in yeast breads, regulates action of yeast

Question 20

What is the role of leavening agents in a baked product and what are 4 examples?

Answer 20

• produce gas in batter to make it more light and porous

- Yeast, baking powder, steam and air

Question 21

What are the general objectives in mixing doughs & batters?

Answer 21

• uniform distribution of ingredients

- optimum blending and development

Question 22

Define what components are in the following:
whole grain
whole meal
cereals

Answer 22

whole grain - bran + germ
whole meal - bran, no germ
cereals - wheat/rice, no germ