Cereals and flour

Question 1

Winter wheat

Answer 1

grain wheat grown in UK, weak flour 10% protein, cakes and baking

Question 2

spring flour

Answer 2

Spring, Canada and America, 12-14% protein, strong flour, bread

Question 3

Durum wheat

Answer 3

high protein hard wheat, pasta

Question 4

Bran

Answer 4

outer coat, 15% grain weight, high b vitamins, and 50% minerals, >90% fibre (cellulose)

Question 5

Germ

Answer 5

base of grain, 20% weight, rich in fat, protein, phyochemicals, b vitamins, E vitamins, iron
Scutellum separates germ from endosperm, rich in thiamin

Question 6

Endosperm

Answer 6

Mainly storage carbohydrate, encased in protein rich aleurone layer

Question 7

Milling traditional

Answer 7

fixed stone
other stone moves from wind/water
ridged/gap between stone
bran sieved to produce white

Question 8

roller milling

Answer 8

chilled iron rolls
one faster, faster one holds, other strikes
do not crush, shear away from white from brown outer skins
if crushed, discolourizes
sorted by sifting

Question 9

plan sifter

Answer 9

10-12 large sieves in layers, coarsest at top

swing briskly

Question 10

purifier

Answer 10

sieving and air currents
separate by size and weights
skins lighter than flavoury endosperm

Question 11

Extraction rate

Answer 11

yield of flour obtained from wheat in milling process
wholemeal = 100%
white = 70% etc

Question 12

wholemeal flours have

Answer 12

increased fibre, vitamins and minerals, phytochemical, protein
decreased carbohydrate

Question 13

law requires fortification of all flours other than wholemeal

Answer 13

1.65mg iron/100g
0.24mg thiamin/100g
1.6mg niacin/100g
235-390mg calcium/100g

Question 14

types of flour

Answer 14

brown = 85%
white = 70%
wheatgerm = brown/wholemeal 10% wheatgerm added
malted wheat germ: brown/wholemeal added malted grains
stone ground: traditional
organic

Question 15

Agglomerated

Answer 15

flour particles fall through jets of steam, then cold water
oute surface wetted, particules clump together
gives dust free flowing flour used as thickening agent on soups and gravy

Question 16

self-rising flour

Answer 16

weak poor dough with yeast

acidic rising agents and sodium bicarb added so co2 produced during cooking to areate dough

Question 17

Enzymes in flour

Answer 17

1. a-amylase
   - not naturally in flour
   - endo-enzyme
   - decreases viscosity
   - important in germination cereals
   - degrade ungelatinised starch slowly

Question 18

B-amylase

Answer 18

-naturally present in wheat flour
-exo-enzyme
important in fermentable sugars

Question 19

gas production

Answer 19

damaged starch granules are more accessible to enzymes
-milling effect
-adequate damaged starch needed for CO2 production
-too much damage decrease loaf volume
amylase in flour: starch - maltose
maltase in yeast: maltose - 2 x glucose

Question 20

Dough development

Answer 20

gliadin 
glutenin
high proportion of -SH and S-S bonds in protein 
during hydration and mixing
gliadin and gluten form gluten
gluten is an elastic protein 
long glutenin gives strength
small gliadin gives extensibility
hydrogen bonds cross link
hydrophobic/hydrophylic interactions with galacto syl lipids

Question 21

Bread staling

Answer 21

• crust staling caused by diffusion of water from inside of loaf
• inside loaf becomes less elastic

Question 22

Reducing staling

Answer 22

• dry bread and wet bread reduces staling
• temp 60C
• wrapping
• emulsifying agents