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Cookery and Nutrition Beginners
Carbohydrates
This is a group of foods which contains starch, NSP (dietary fibre) and sugar.
Carbohydrates are usually plant products.
Carbohydrates
STARCH
We should eat plenty of starchy
cereal foods. Such as: rice oats,
barley, maize and rye and
starchy vegetables like potatoes
and squash.
1.
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SUGAR
NSP
Starchy foods like wheat, rice
and other cereals are usually
‘wrapped in fibrous cell walls
made up of NSP (bran).
WE should not get more than
10% of our daily energy from
sugars. These are called
empty foods, because they
just provide us with energy
and nothing else. (There is
not nutritional advantage of
using brown sugar.)
Functions of Carbohydrates in the diet
Supply the body with 45% of the energy.
Contribute to the cell structure
Keeps us warm
If carbohydrates are taken for energy, proteins can do their
primary functions of body building rather than energy. This process is
called Protein sparer.
2. Characteristics
 Daily energy intake from Carbohydrates should be 45% whilst that of sugar less
than 10%.
 1 gram of carbohydrates is 4 Kilo Calorie.
 Found mainly in plant origin foods.
 Are the cheapest to buy.
 Vitamin B helps the breakdown of Carbohydrates.
 Made up from a carbon, hydrogen and oxygen.
Sugars
1. Classification of sugars:
 Monosaccharide: composed of 1 sugar unit. Called simple sugars.
Fructose: mainly found in fruits (and honey).
Glucose: found in ripe fruit and some vegetables.
Galactose: found in milk of mammals.
 Disaccharides
Two monosaccharide joined together.
Sucrose: 1 glucose + 1 fructose. Used in cookery(cane sugar)
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Cookery and Nutrition Beginners
Lactose: 1 glucose + 1 galactose. Found in milk of mammals.
Maltose: 1 glucose + 1 glucose. Found in cereals.
2. Sugars can be classified as Intrinsic and Extrinsic sugars.
 Instrinsic: those who are naturally part of the cellular structure of foods for example fruit. These
have no bad effects on health and teeth.
 Extrinsic: not contained within the cell walls. These may be natural such as honey, or refined such
as granulated sugar. These are called Hidden sugars.
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3. Sources of Sugars
Milk
• Fruit and vegetables
Honey
• Cereals
Table sugar
• Icing sugar
Jams
• Chocolate
Ice-cream
4. A diet high in sugar can lead to:

Tooth decay
Sugars are the major cause of tooth decay. When sugar is eaten, acid is produced
which attacks the enamel surface of the tooth, gradually causing a hole. If the
acids are allowed to stay in the mouth for long periods of time, tooth decay
develops.

Obesity
Sugary foods give lots of energy because they are high in calories and low in
fibre. Eating too much of these foods means that excess is stored as fat, leading
to an increase in body weight.

Diabetes
This is a condition in which the body (pancreas) is not able to convert,
or becomes less efficient in converting, glucose in the blood into
energy. As a result, the amount of glucose in the blood starts to rise.
Glucose is obtained from the digestion of carbohydrates.
Eat carbohydrates
Rise in blood glucose level
Insulin (produced in the _________) to controls level of glucose in
blood
Starch
Starch is formed by many glucose units joined together, as they
are more complex than sugars it is called complex carbohydrates.
1. Importance of starch in the diet:
 Starch is very healthy and helps to keep blood sugar levels constant.
 Starchy foods provide other nutrients as well as starch such as calcium, iron, B
Vitamins.
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 When we eat more starchy foods it helps to cut down on fatty foods as starch fills us
up quickly.
Protein
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Proteins are made up of long chains of building block called amino acids.
1 gram of protein gives us 4 Calories
Protein should be 15% of our daily energy intake
1. The functions of protein
Every cell in our body contains some protein. Protein is needed
for growth and repair of body tissue, muscles and blood cells.
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2. Essential and Non- Essential Amino Acids
There are 20 amino acid which make up proteins.
Our bodies can make eleven amino acids; therefore they are called- NON- ESSENTIAL
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AMINO ACIDS/Dispensable Amino Acids.
We need to obtain other nine amino acids and these are called ESSENTIAL AMINO ACIDS/
Indispensable Amino Acids.
3. Sources of proteins
 ANIMAL ORIGIN
Meat, fish, poultry, eggs,
milk and milk products.
These contain all the
essential amino acids.
 PLANT ORIGIN
Peas, beans, lentils, cereals, nuts and seeds.
These foods tend to lack one or more of the
essential amino acids. However, there is an
exception – Soya beans contain all of them.
4. Novel Sources of protein
Soya beans are used to make T.V.P.-Textured Vegetable Protein which is shaped,
flavoured and coloured to look like meat. This is suitable for vegetarians.
Qourn which is made from mycoproteins. They are high in protein and
low in fat, used as alternatives to meat.
Tofu: is a foodmade by coagulating soy milk, and then pressing the resulting curds
into blocks.
5. Complementary proteins
 LOW BIOLOGICAL VALUE- LBV.
Vegetables foods which are good source of protein usually lack one or more of the
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essential amino acids needed by humans, so proteins from a single vegetable food are said to
have a low biological value- LBV.
Mixtures of proteins from plant foods taken together can complement each other
by supplying the full range of amino acids needed by humans.
Example of complimentary protein meals are:
♥Beans on toast
♥ Rice and peas
♥ Kidney beans and rice
 HIGH BIOLOGICAL VALUE, HBV.
Animal protein from meat, fish, milk, cheese and eggs supply all the essential amino acids and
are said to have a high biological value, HBV.
6. Protein
8. Dangers of high protein slimming diets
 The human body needs a source of energy and carbohydrates are the best source of
energy available to us. In the absence of carbohydrate, the human body is forced to burn
dietary fat (therefore you will lose weight) and protein to fulfill its energy needs.
 The breakdown products of burning large quantities of body fat for fuel are called ketones.
They will begin to accumulate in the body.
 A build-up of ketones in the body can cause all kinds of damage to vital organs such as the
liver and the kidneys.
 This process is called ‘ketosis’.
Fats and Oils
o Fats are solid at room temperature while oils are liquid at room temperature.
o Fats are made out of 3 elements which are carbon, hydrogen and oxygen.
o Fat is present in food either as visible (that can be seen) or invisible (that
cannot be seen).
1. Types of fats
Fats are made of Essential Fatty Acids (EFA’S). Fatty acids are the building blocks of the fat in
our bodies and in the food we eat. During digestion, the body breaks down fats into fatty acids,
which can then be absorbed into the blood. Fatty acids have to be ingested since the body
cannot produce these.
a. Saturated fats
Are found primarily in animal products – red meat, lard, butter, poultry
with skin and whole milk dairy products. Saturated Fats are also found in
plant products such as: vegetable oils; palm and
coconut. Avocado fruit also contains saturated fat.
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b. Unsaturated fats
Monounsaturated fatty acids are found mainly in plant fats and oils especially olive oil and
polyunsaturated fatty acids are found mainly in vegetable oils and fish oils.
Omega Fatty Acids
Omega-3 fatty acid is an essential fatty acid that plays an
in brain function and may help you fight against cardiovascular
Sources: Grains, Brazil Nuts, Mustard Seeds, Pumpkin Seeds,
Vegetables, Walnuts, Fish Oils, and flaxseed.
important role
disease.
Green
Leafy
Omega-6 plays a crucial role in brain function, as well as normal growth and development.
Sources: Olive Oil, Sesame Oil, Pumpkin Seeds, Safflower Oil, Sunflower Oil, Raw Nuts &
Seeds.
Trans fatty Acids (Trans fats/ TFA) and Hydrogenation
Trans fats are made by a chemical process called hydrogenation.
Liquid vegetable oil (an otherwise healthy monounsaturated fat) is
packed with hydrogen atoms and converted into a solid fat.
This is common in margarine and shortening. These fats also raise
blood cholesterol.
2. Fats recommendation
30% of our energy intake should be supplied from fats. Saturated fats should be less than 10%!
Remember 1 gram of fats gives us 9 kcal.
3. Functions of fats
 It is a good source of energy.
 A layer of fat is stored around certain vital organs protects them from damage
(e.g. kidneys).
 It is needed by all body cells.
 It provides us with Vitamins A, D, E and K.
 Forms an insulating layer under the skin which helps to keep us warm.
 Fat gives a good ____________to foods.
4. What happens if we eat too much fat?
a. We become Obese (Obesity -being very overweight)
 Diets high in fat tend to result in obesity as fat provides a lot of calories.
 Obesity raises blood cholesterol.
 Obesity may also lead to high blood pressure and heart disease. ( stroke, heart
attack, heart failure)
 To lower the blood cholesterol level eat more starchy carbohydrates or unsaturated fats
instead of saturated fats.
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b. High cholesterol level & High blood pressure
 High blood pressure results when the blood has difficulty travelling
through the arteries and veins due to narrowing.
 Arteries harden due to the build up of deposits of cholesterol and other
fatty substances that form plaque and in turn narrow the arteries.
 The heart then finds it difficult to pump blood around the body at the
required rate.
 Untreated high blood pressure may lead to stroke or heart attack.
c. Heart Disease
There is a strong link between the intake of high levels of fats (especially
saturated) in the diet and coronary heart disease (CHD).
What happens?
 A diet high in saturated fats leads to a buildup of fatty deposits on the inner
walls of the arteries, restricting the flow of blood through them.
 If a small blood clot forms in the coronary artery, which takes the blood to the
heart, it can totally block this narrowed artery causing a heart attack.
 A blood clot which blocks the artery leading to the brain can cause a stroke.
Vitamins
Fat soluble
Water Soluble
 Vitamin B
 Vitamin A
 Vitamin C
The water soluble vitamins dissolve in
water and tend to be excreted every day
in urine. This means that foods rich in
these vitamins need to be eaten regularly.
Water-soluble vitamins cannot be stored
in the body.
 Vitamin D
 Vitamin E
 Vitamin K
Fat-soluble vitamins can usually be
stored in the body in the liver.
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1. Water Soluble Vitamins
Vitamin
Function
Good sources
Deficiency
Thiamin (B1)
Helps the release of Fortified
breakfast
energy from nutrient in cereals, meat, liver,
every cell in the body.
milk
and
milk
products, eggs and
vegetables
including
potatoes.
Slows
growth
and
development.
Mild
deficiencies
cause
tiredness
and
depression. Sever causes
beriberi.
Riboflavin (B2)
Needed for healthy
skin. Helps the release
of energy to cells and in
the body’s use of
carbohydrates.
Slows down growth and
development.
May
cause skin and eye
problem.
Niacin (B 3)
Involved in the energy Meat, especially offal, Sever deficiency causes
producing reactions in cereals, potatoes and pellagra.
Symptoms
cells. Helps the nervous bread
include
diarrhoea,
system and healthy skin.
dementia
and
dermatitis.
Cereals, nuts, milk and
milk products, meat,
liver kidney, eggs, lean
meat
and
green
vegetables.
All animal foods- liver,
Helps prevent certain fish, meat, cheese, milk Can lead to anaemia and
forms of anaemia. Helps and eggs. Fortified neurological problems.
cells to divide.
breakfast cereals.
B12
Folic acid (b 9)
Deficiency in the early
stages of pregnancy is
associated with several
tube defects. Needed for
red
blood
cells
production
Meat, especially offal,
shellfish,
cereals,
beans, legumes and
dark leafy vegetables.
Mild deficiency leads to
tiredness. A deficiency
may cause anaemia.
Needed in pregnancy to
prevent neural tube
defects, such as spina
bifida.
VitaminCAscorbic Acid
Maintains
body’s
connective
tissue,
important for wound
heeling. Helps iron
absorption.
Fruits and vegetables,
especially citrus fruit
including oranges and
lemons.
Scurvy
(Antioxidant)
Vitamin B helps the release of energy from carbohydrates.
Scurvy: swollen and bleeding gums with loosened teeth, soreness and stiffness of the joints and lower extremities, blee
under the skin and in deep tissues, slow wound healing, and
anaemia.
Ms.
J. Borg
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Cookery and Nutrition Beginners
What are the effects of heat on B complex Vitamins and Vitamin C?
Most of the B Vitamins except Niacin are sensitive to heat so can be lost by cooking.
They can also be lost by dissolving into cooking water. Thiamin (Vitamin B1) and
Vitamin C (ascorbic acid) are the most easily lost of all the vitamins.
Vitamin C is quickly and easily destroyed by:

Heat

Exposure to air

The presence of alkali such as bicarbonate of soda

Water
2. Fat Soluble Vitamins
Vitamin
Vitamin ARetinal
Use by the body
Good sources
Deficiency
Good for night
vision, healthy skin
and tissue.
Animal origin- liver,
oily fish, milk, butter,
margarine and cheese.
Long-term
deficiency may
lead to night
blindness.
Excess may
lead to liver
and bone
damage.
Beta carotene (Antioxidant)
Vitamin D - Cholecalciferol
Vitamin E- Tocopherol
(Antioxidant)
Is an antioxidant
vitamin which
might protect
against cancers
Helps the
absorption of
Calcium to from
healthy bones and
teeth.
Vegetable origincarrots, green
vegetables, orange and
red fruit and
vegetables.
Mostly available by
exposure to sun.
Found in margarine,
oily fish, and liver.
Good for healthy
skin. May help to
protect against
hearth disease
Ms. J. Borg
Eggs, nuts, seeds,
cereal products,
vegetable oils.
Deficiency in
children can
cause rickets.
Deficiency
rare.
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Cookery and Nutrition Beginners
Vitamin K- Phylloquinone
Involved with
clotting blood
Green vegetables,
pulses, fruit and
cereals, meat, liver.
Also made by bacteria
in the large intestines.
Deficiency
rare.
Antioxidants (Vitamin A, C and E)
They are vitamins, minerals, and other nutrients
that protect and repair cells from damage caused
by free radicals. Many experts believe this damage
plays a part in a number of chronic diseases,
including hardening of the arteries, cancer, and
arthritis.
Rickets: softening of
bones in children
potentially leading to
fractures and deformity.
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