Cereals

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Cereals
The grains of cultivated grasses
© PDST Home Economics
Cereals
Wheat
Rice
Maize
Oats
Rye
Barley
Structure of Cereal Grain
Bran layer 14%: fibre,
vitamin B, calcium, iron.
Endosperm 84%:
Starch, protein, vitamin
B.
Germ 2%: protein, fat,
vitamins B & E, iron.
Average Composition of Wheat
Protein Fat
Carb. Vitamins
Minerals
Water
12%
72%
1%
Calcium
Iron
12%
2%
1%
B&E
Nutritive / Food Value
Protein, LBV, (gluten in wheat and rye).
Fat, polyunsaturated, essential fatty acids.
Carbohydrate, starch mostly, the rest is fibre.
Vitamin B especially B1, B2, niacin, also Vitamin E.
Minerals: Calcium Iron, Phosphorus.
Low in water therefore they keep well.
Dietetic Value
Important energy food because of starch.
Whole grains good for fibre.
Wholegrains good source vitamin B calcium, iron.
Unsaturated fat ok in low cholesterol diets.
Cheap & versatile.
Coeliacs must avoid wheat, oats, barley, rye because of
gluten.
Phytates in cereals inhibit calcium & iron absorption.
Polished rice lacks Vitamin B and maize lacks tryptophan
so deficiency diseases can occur where they are the
staple food.
Effects of Heat on Cereals
Starch grains swell, burst, absorb liquid (e.g. risotto).
Dry heat: grains swell burst and absorb fat (e.g. pastry).
Cellulose gets soft.
Starch becomes digestible.
Protein coagulates (e.g. sets dough in oven).
Dextrinisation and caramelisation causes surface browning
on bread and cakes etc…
Loss of some vitamin B.
Buying and Storing Cereals
Buying
Sealed package
Date stamp
Storing
Seal in storage container
when opened
Cool dry dark press
Use by best before date
Wholegrains go off
faster because of fat
present
Types of Wheat:
most flour is made from a mixture of wheats
Spring wheat
Sown in March,
harvested in
September.
Grown in climates with
cold winters, hot
summers.
Fast growing.
High gluten content.
Winter wheat
Sown in autumn,
harvested late
summer.
Grown in temperate
climates (Irl).
Slow growing.
Low gluten content.
Flour Milling
Cleaning: sieved and washed
Conditioning: correct moisture
content
Blending: grist made
Break rolling
(wholemeal flour made)
Sifting and purifying: bran and
germ separated from rough
endosperm (semolina)
Reducing: rough endosperm
ground into powder
Air classifying: to lighten
Addition of additives: calcium,
vitamin B, bleach, improvers
Packaging
Types of Flour
Flour Type
Extraction
Rate
Description/Use
Stoneground
100%
Ground between stones
Wholegrain
100%
Non of the grain removed
Wheaten / brown 85%
A lot of bran removed
White /plain/
cream
75%
All bran and germ removed
Self-raising
<75%
White flour and raising agent
Strong flour
<75%
Higher % gluten
Gluten free
High-ratio
Gluten removed for coeliacs
< 50%
Soft fine flour, for
confectioners
Effects of Processing
Whole grain flour has more protein than white.
White has no fibre.
White flour has no fat therefore keeps for longer.
White flour is fortified with calcium and Vitamin
B.
The more processing, the softer the texture.
Bleaching agents are used to whiten colour.
Elasticity of the gluten is increased by adding
improvers. White flour rises better than
wholegrain.
Cereal Products
Cereal
Wheat
Rice
Products
Flour, semolina (couscous), pasta, weetabix and
other breakfast cereals.
Ground rice, rice flour, rice wine, rice cakes,
Rice Krispies, rice paper.
Maize/corn Corn on cob, sweetcorn, maize meal, corn
flour, corn oil, popcorn, cornflakes.
Oats
Oatmeal, pinhead oats, rolled oats for
porridge and muesli, oatmeal biscuits.
Rye
Rye bread, crispbread, whiskey.
Barley
Pearl barley, barley water, whiskey.
Pasta
Rough endosperm
(semolina) of durum wheat
+ water + salt + oil + egg +
colouring(spinach, tomato,
squid ink, wholemeal).
Made in many shapes.
Sold fresh or dried.
Breakfast Cereals
Wide variety made from
different grains.
Flaked, shredded, puffed.
Other ingredients added;
dried fruit, honey, nuts,
cocoa sugar, salt.
Often fortified with vitamins
and minerals.
Nutritive value depends on
ingredients and the milk used.
Porridge, muesli, high bran
cereals are good.
Rice
Less protein, fat and
minerals than other
cereals.
Usually used with bran
removed (polished).
Many varieties.
Varieties of Rice
Short grain (Carolina,
pearl, pudding) used in
milk pudding.
Medium grain (Italian,
arborio), used in risotto.
Long grain (Patna,
Basmati), used with curry
and other dishes
Brown, only some bran
removed, nutritious, used
like long grain but takes
45 minutes. to cook.
Cereal
Grains
Wheat
Rice
Maize
Oats
Rye
Barley
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