Functions of ingredients

Flour:

• Provides fibre (especially if wholemeal)
• If Self-Raising, makes mixtures rise
• Thickens sauces
• Forms the bulk of bread, pastry and cake mixes
• If wholemeal, provides colour and texture
• Gluten in flour produces a stretchy dough
• Provides carbohydrate, Vitamin B, calcium and iron

Sugar:

• Provides sweetness
• If brown, provides colour and texture
• Large amounts prevent micro-organism growth (for example, jam/marmalade)
• Caramelises to produce a brown colour
• Retains moisture
• Helps to trap air in cake mixtures
• Provides carbohydrate

Eggs:

• Hold air when beaten
• Coagulate (sets) when heated
• Add colour to mixtures
• Thickens sauces, custards, etc.
• Glaze bread, scones and pastry
• Bind ingredients together
• Provide protein, fat, iron and Vitamins A, B, and E

Fats/Oils:

• Provide flavour
• Keep products moist and extend shelf-life
• Add colour to foods
• Make pastry 'short' by coating the flour to stop gluten developing
• Hold air when creamed with sugar
• Oil forms an emulsion with liquids (for example, mayonnaise)
• Provide energy and Vitamins A and D

Nutrition

Fats:

• Gives energy and vitamins A, D, E and K
• Found in oils, solid fats, fatty meat, cream, cheese and nuts
• Animal fats and some vegetables oils contain saturated fat, which may raise blood cholesterol levels
• Vegetable fats such as sunflower and soya and those in oily fish are polyunsaturated and better for the heart
• Gives a rich source of energy that can be converted into fat in the body, which protects organs and gives heat

Carbohydrates:

• Provides energy and fibre
• Found in cereals, vegetables, sugar, rice, pasta, bread and pastries
• If the body receives more energy than it needs, it stores it as fat
• Wholemeal/wholegrain cereals are a richer source of fibre than white/refined ones
• Vitamins B and E, calcium and iron are also provided by bread

Proteins:

• Enables the body to grow and repair
• Found in milk, meat, fish, eggs and cheese
• Also in soya, beans, cereals, pulses and nuts
• If more protein is eaten than is needed for growth and repair, the excess is converted into glycogen in the liver and used as energy
• Animal foods and soya beans are used most efficiently by the body
• Many protein foods also provide iron and B vitamins (especially B12)
• Tofu (soya bean curd), Textured Vegetable Protein (TVP) made from soya flour, and Quorn (fungus) can all be used to replace animal proteins

Vitamins:

• A: Fat-soluble

  Helps with night vision. Keeps the linings of the nose, throat and digestive system moist. Found as carotene in orange and red fruits and vegetables. Found as retinol in oily fish, liver, butter, margarine, cheese and eggs. Other sources include, mango, spinach, carrot, sweet potato. Excess may lead to liver damage.

• B: Water-soluble

  Thiamin (B1), Riboflavin (B) and Niacin are involved in the release of energy from foods, healthy nervous system and skin. B12 helps prevent birth defects, such as Spina Bifida and is needed for red cell production. Found in marmite, meat, nuts, green leafy vegetables, yeast and dairy products.

• C: Water-soluble

  Needed for the formation and maintenance of connective tissue. Helps wounds to heal, helps prevent infections and aids iron absorption. Found in fruits and vegetables, especially citrus fruits, potatoes, broccoli, blackcurrants and kiwi fruit.

• D: Fat-soluble

  Produced by the action of sunlight on the skin. Needed for the absorption of calcium in the bones and teeth. Found in butter, margarine, cereal, milk and fish. Excessive intakes can be dangerous.

• E: Fat-soluble

  May be necessary for reproduction. Helps keep skin healthy. Found in eggs, wholegrain cereals, almonds, sunflower seeds, vegetable margarines and oils.

• K: Fat-soluble

  Involved in the clotting of blood. Found in green vegetables, meat, beans, fruit and cereals.

Minerals:

The amount of nutrients required depends on 4 factors:

• Sex
• Age
• Activity
• Special conditions

Measuring the amounts of nutrients needed...

• DRV (Dietary Reference Values): Estimates of the nutritional requirements of different groups of healthy people of different ages.
• EARs (Estimated Average Requirements): Estimation of the needs of most people in a particular group.
• RDA (Recommended Daily Allowance): Often used on packaging to indicate whether or not a food product is a good source of a particular nutrient.
• RNI (Reference Nutrient Intake): Amount of a nutrient, which will satisfy 97.5% of the population in a particular specified group.

Healthy eating targets...

• 1: Energy obtained from total fat intake should be no more than 35% of the total energy intake.
• 2: The energy obtained from saturated fat should be reduced to 11%.
• 3: Obesity in people aged between 16-64 years should be reduced by a quarter in men and a third in women.
• 4: Blood pressure should be reduced by people cutting down on their intake of salt and alcohol.