The Importance of a Balanced Diet and Food Safety

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Eatwell Plate

A balanced diet:

  • Provides energy to survive.

  • Growth and repair of body tissue.

  • Bodily function.

  • Stopping us feeling hungry

  • Health and wellbeing.

5 food groups:11

  • Fruit and vegetables.

  • Starches

  • Proteins 

  • Dairy products

  • Fats and oils

The Eatwell Guide applies to everyone regardless of weight, dietary restrictions or ethnic origin.

It doesn’t apply to children under 2 years because they’ve different nutritional needs. 

Fruit and vegetables

  • Fruit and vegetables → ⅓ of food that we eat each day.

  • Eat at least 5 portions of fruit and vegetables.

  • Choose → fresh, frozen, canned, dried or juiced.

Potatoes, bread, rice, pasta and other starchy carbohydrates

  • Starchy food → ⅓ of food we eat per day.

  • Choose → higher-fibre, whole grain → contains more fibre and other nutrients, digests slowly (helps us feel full for longer. Increase fibre intake

Beans, pulses, fish, eggs, meat and other proteins (important)

  • Sources of protein, vitamins and minerals.

  • Beans, peas and lentils → good alternatives to meat.

  • Low in high, high in fibre, protein, vitamins and minerals.

  • 2 portions of fish a week, a portion of oily fish.

  • Some type of meat → high in fat (saturated fat).

  • Type of cut and way you cook meat → make difference.

  • No more than 70g of meat per day.

Dairy and alternatives

  • Have some milk and dairy food → cheese, yoghurt and fromage frais.

  • Good sources of protein, vitamins and calcium. (helps to keep our bones strong).

  • Some dairy food → high in fat and saturated fat. Lower fat too

Oils and spreads

  • Some fat in your diet is essential (a small amount).

  • Unsaturated fats → healthy fats (from plant sources).

  • Unsaturated fats → reduce cholesterol in blood, and saturated fat intake.

  • All types of fat → high in energy (limited in diet)


  • Drink – 6-8 glasses of fluid every day.

  • Water, lower fat milk, sugar-free drinks, tea, coffee.

  • Fruit juices and smoothies (free sugars) → limit consumption 150ml per day.

  • Sugary drinks → excess sugar amongst children and adults in the UK.

  • Consumption of no added sugar to reduce sugar intake.

Foods high in fat, salt and sugars

  • Chocolate, cakes, biscuits, full-sugar soft drinks, butter and ice-cream.

  • Not needed in the diet. (small amounts)

  • Limit their consumption

  • Contains lots of energy.

  • Avoid foods → high in fat, salt and sugar.

  • Have a diary (lower fat and lower sugar).

Food safety


  • Single-celled microorganisms.

  • Present → air, soil, on animals and humans.

  • Some foods —> contain microorganisms.

  • Can be transferred to food by poor hygienic practices.

Function: Harmless bacteria are used in food manufacture. (making cheese and yoghurt)

Spoilage: Bacteria are often undetected because food looks, tastes and smells as it should. Food poisoning bacteria → pathogenic bacteria (very harmful).

Conditions needed for growth

  • Active → warmth, moisture, food and oxygen. (high-risk foods)

  • Reproduce rapidly by dividing.

  • Grow rapidly in neutral pH conditions.

  • Active in a temperature range of 5-65 degrees (danger zone).

  • Best temperature → 37 degrees (human temperature).

  • Cannot survive → 70 degrees or above.

  • Some are able to form spores.


Function: Harmless moulds used in food manufacture (blue-veined cheese).

Spoilage: Visible to the eye: moulds grow on the surface of food. They can be black, white or blue. Moulds reproduce by producing spores.

Conditions needed for growth

  • It Grows quickly in the moist.

  • Temperatures of 20-30 degrees.

  • Mould grows slowly in dry, cold conditions.

  • Grows on foods that may be dry, moist, acid, alkaline or have salt or sugar concentrations.


Function: through the process of fermentation yeasts are used to make breads and alcohol. Yeasts are responsible for food spoilage in high-sugar foods such as fruit, jam and fruit yoghurt.

Conditions needed for growth

  • Active in warm, moist conditions with food for growth and reproduction.

  • Not oxygen needed for growth.

  • Anaerobic growth.

Helpful properties of microorganisms

  • Not all microorganisms are harmful.

  • Probiotic foods contain live bacterias.

  • Good Bacterias → friendly bacterias.

  • Enzymes are used in manufacturing processes:

-    Bread and brewing, cheese and ripening stage

Food spoilage

  • Food not preserved → deteriorates (unfit to eat).

  • Deterioration is caused by → organisms and enzymes

  • Food preservation → increases the shelf life

Buying food

  • Food is in danger of becoming infected at each stage of its production.

  • Poor hygiene → contaminated (food poisoning).  Buy food from a reputable shop.

Storing food

  • Food → stored correctly.

  • Refrigerators: should be between 0 and 5 degrees. Growth of food poisoning bacteria is slowed down in a refrigerator.

  • Freezers and freezing: be kept at -18 degrees. Food poisoning bacteria are dormant in a freezer.

Rules for food hygiene

  • Wash your hands before handling food.

  • Keep raw and cooked foods separated.

  • Use different and clean equipment.

  • Wear clean protective clothing, cover cuts, never cough or sneeze over food.

  • Cover and cool all cooked food rapidly.

  • Store below 5 degrees.

  • No hot foods in the refrigerator.

  • Pets away from food.

  • Keep flies out of the kitchen.

How do bacteria get into food?

  • Pathogenic bacteria → food poisoning

  • Contamination occurs because of:

  • Poor hygiene during production and serving of food.

  • Cross-contamination between raw foods and cooked foods.

  • Storage of high-risk foods.

  • Poor preparation and cooking routines such as:

  • Not thawing foods properly.

  • Preparing food far in advance.

  • Undercooking high-risk foods.

  • Not allowing foods to cool.

  • Not reheating foods to the correct temperature for a long enough time. Not checking temperature accurately with probe

  • Leaving food on display at room temperature. Hot foods below 63 degrees

Preventing cross-contamination

  • Microorganisms can transfer from raw to cooked food, causing infection.

  • To prevent cross-contamination:

  • Avoid raw and cooked food that touch each other.

  • Avoid the blood and juices dripping onto cooked food.

  • Avoid bacteria to be transferred during handling or preparation.

Why has there been an increase in cases of food poisoning?

  • People are using microwaves often (food is not cooked at correct temperatures).

  • Increased use of cooked-chill (high-risk food).

  • Foods not stored at the correct temperatures.

  • Food not prepared correctly.

  • Poor personal hygiene.

Why has there been an increase in cases of food poisoning?

  • People are using microwaves often (food is not cooked at correct temperatures).

  • Increased use of cooked-chill (high-risk food).

  • Foods not stored at the correct temperatures.

  • Food not prepared correctly.

  • Poor personal hygiene.

High-risk and low-risk foods

  • Have high protein and moisture content.

  • Raw fish

  • Dairy products

  • Cooked meat and poultry

  • Selfish meat and poultry

  • Gravies, sauces, stocks, soups and stews.

  • Egg products

  • Cooked rice

  • Protein-based baby foods

Low-risk foods

  • High acid content foods

  • High sugar content foods

  • Sugar-based confectionery

  • Unprocessed raw vegetable

  • Edible oils and fats


Possible source


Poultry, eggs, meat

Staphylococcus aureus

Food handlers

Clostridium perfringens

Raw food such as vegetables and meat

Bacillus cereus

Cereals, especially rice


Infected animals, birds and unpasteurised milk.


Raw, processed and cooked foods, for example soft cheese.

E. Coti

Cattle, raw meat and raw milk.

How do bacteria grow?

  • Multiply or reproduce by binary fusion.

  • They require the follow conditions:

  • Warmth (37 and 63 degrees) (72 degrees → kill bacterias)

  • Moisture (dried foods have long shelf life)

  • Food (high in protein and are moist)

  • Time (multiply quickly).

Factors affecting food choice

Healthy balanced diet

Eating the right balanced diet of a wide range of food provides energy and nutrients that they need to stay healthy.

A healthy balanced diet with regular physical activity helps people to maintain a healthy weight and reduce their chance of developing illness.

Factors influencing food choice

A balanced diet depend on many factors:

  • Individual energy and nutrients needs

  • Health concerns

  • Portion size

  • Cultural or religious practices

  • Cost

  • Social and economic considerations

  • Food availability

  • Food preferences

  • Environmental and ethical considerations

  • Advertising and other point of sale information

Individual energy and nutrient needs

The amount of energy, carbohydrate, fat, protein, vitamins and minerals needed varies between the different range of age and between males and females. Energy needs also depend on activity levels. Athletes will have much higher energy requirements due to their high level of physical activity.

Health concerns

Diets which exclude many foods due to a person’s health concerns or for medical reasons need to be planned carefully.

Factors affecting food choice

Healthy balanced diet

Eating the right balanced diet of a wide range of food provides energy and nutrients that they need to stay healthy.

A healthy balanced diet with regular physical activity helps people to maintain a healthy weight and reduce their chance of developing illness.

Portion size

  • Balanced diet → getting the right] amount of food and drinks.

  • Portion sizes are important when making food choices

  • Follow a health, balanced and varied diet.

  • Guidelines → Eatwell guide for all range of people.

Cultural or religious practices

Ethical and religious practices → limit the range of food that people eat.

A vegan will not consume any meat product. They should choose other products to get the meat sources.


The cost of food will influence the people’s food choice.

If money is limited → people will buy basic items and luxury items may be used for special occasions.

Food prepared at home → cheaper

Food availability

Most food is grown in a particular season of the year. (strawberries → summer)

These are called → seasonal foods

Buying food when it is in season → cheaper

Technology has allowed food to be available all year round.

Frozen foods as vegetables are great alternatives to fresh.

Food preferences

Not everyone likes the same food, but some are popular and unpopular. The taste, texture or appearance of foods can affect. People should choose a balanced diet choosing the food they enjoy.

Environmental and ethical considerations

The impact of food production on the environment can be of a high social concern for some people.

Some considerations when buying food might be:

  • Fair trade

  • Buying local food (supports local business and farmers).

  • Genetically modified food (intervention of a plant animal or microorganism’s genes or insert one gene from another organism)

Advertising and other point of sale information

  • Encourages people to choose certain foods.

  • Television, internet, radio, posters, magazines and newspapers.

  • Provide information to consumers.

  • Healthier choices

Other sources of information

Sources to help people when making food choices:

  • Department of Health

  • NHS choices

  • British Nutrition Foundation

  • Supermarkets, food manufactures, charities, etc.

  • The media (internet)

Important → look for the info Standards logo.

Info required on the labels of pre-packed food and drinks products:

  • Name of the product

  • List of ingredients (including additives)

  • Weight or volume

  • Date mark

  • Storage and preparation conditions

  • Name and address of the manufacturer, packer or seller.

  • Country of origin and place of provenance.

  • Nutrition information.

Choux pastry


Function of ingredients


75g strong plain flour

High gluten content

Stretches to hold the expanding steam and air.

Carbohydrate - Energy

50g Butter

Added for flour

Fat- gives warmth

125 ml Water

Boiled to 100 degrees  causes the flour to gelatinise and develop gluten. Water also creates steam whilst cooking in the oven which expands causing the mixture to rise.


2 eggs

Hold the air from the steam in the mixture. Gives smooth, glossy finish and aids piping of mixture.

Protein - Growth and repair

Proportion fat to flour

1:1,5 (accuracy -key to success)




  • Denature

  • Coagulation

  • Coagulate

  • Setting

Amount of portion required / day → RNI → 0,75 x ½ g of body weight.

Protein egg gives → 6g = 70 colonies

Lion mark on an egg

  • Shows that an egg has been produced to the highest food safety standards.

Inside of an egg

Food values of eggs

  • Micro nutrients are vitamin A → importance for normal vision, the immune system and reproduction. Also helps organs (like heart, lungs).

  • B12 → needed for iron absorption.

  • Iron

  • Don’t contain any carbs or vitamin C.

Function of eggs

  • Trap air

  • Blind ingredients together.

  • Coat products to protect them when cooking.

  • Thicken products

  • Prevent oil + water separating.

  • Glaze products

  • Enrich products Garnish products

Milk and milk production

Homogenised milk

Processing of food

Primary processing; Change a basic food to preserve it or prepare it for sale or cooking.

Secondary processing: Using a primary processed food to make into another product.

Pasteurised milk

Is a raw milk that has been heated to a specific temperature and time to kill pathogens.

Bacteria → raw milk 71.7 degrees for 15 seconds.

  • Pathogens → microorganisms such as bacteria that make us sick (food poisoning).

  • Vitamins A and D → added to milk, no more additives added to milk.

Sterilised milk

  • Sterilised milk is heated between 120 degrees and 135 degrees.

  • No preservatives involved.

  • Nutritional value → same as fresh milk

  • Sterilised milk has a slightly sweeter taste than fresh milk. (due to the heat treatment).

UHT milk - Ultra heat treatment

  • UHT, milk is ultra-pasteurized milk in sterilised containers.

  • It’s real milk, but it has a special pasteurisation and packaging process, which gives a shelf life.

  • Kills bacteria in the milk that may be harmful, or cause milk to spoil.

  • UHT milk can sit out unrefrigerated for about 3 months. Once the container is opened, the milk should be refrigerated.


  • Micronutrient

Two groups of vitamins: 

  • Fat-soluble

  • Water-soluble

Importance of vitamins

  • Maintain health

  • Regulate the repair of body cells

  • Help energy to release.

  • Prevent deficiency diseases.

  • Help our immune system.

Antioxidants help our body against ‘free-radicals’, produced → break down food, tobacco smoke, and radiation for intake.

Thiamin→ B2


  •  Growth

  • Help maintain a normal nervous system.

  • Slows growth and development

  • Help release energy from carbohydrates


  • Fatigue

  • Poor memory

  • Loss of appetite

  • Sleep disturbances

Rivofianin→ Vitamin B2

  • Help to absorb iron.

Deficiency: cause poor growth rate. Skin eye problems.

Niacin → Vitamin B3

Deficiency: rough sore skin, weakness and depression.

Found in: Fish, chicken/beef and turkey.

Vitamin B (folate / folic acid)

Function → helps the body to develop. 

              → Essential for the formation of body cells


  • Tiredness

  • Anaemia

  • Forgetfulness

  • Depression

  • Irritably

Vitamins C and Minerals

Two groups of vitamins: 

  • Fat-soluble

  • Water-soluble

Importance of vitamins

  • Maintain health

  • Regulate the repair of body cells

  • Help energy to release.

  • Prevent deficiency diseases.

  • Help our immune system.

Antioxidants help our body against ‘free-radicals’ which are produced when we break down food, tobacco smoke, and radiation for intake.

Vitamin C (ascorbic acid)


  • Formation of connective tissue.

  • Helps blood and blood vessels formation

  • Absorb iron

  • Healing

  • Calcium - absorption


  • Macronutrient

  • They contain many properties such as fibre and nutrients.

  • Provide a range of minerals and vitamins.  High in fibre

Ways to cook vegetables:

  • Boiled      - Roast in oven   - casserole

  • Stir-fry       - Fried              - storing vegetables: cool dry places

  • Soups        -salads              -potatoes → covered

Storing vegetables:

  • Fresh, crunchy, bright colour

  • Cool dry place

  • Potatoes should be stored covered

  • Leave in the original bag because it has been treated with CO2

Root vegetables → carrots, parship

Tubers → potatoes, sweet potatoes (attached to plant by tubers)

Bulbs → onion, garlic, turnip, celeriac (sits on top of soil and roots go beneath soil)

Steams → celery, asparagus, fennel (eat steam)

Leaves → cvolo, curly kale, sprouts, lettuce

Flower heads → broccoli, cauliflower

Fungi → mushrooms

When they are cooked, they become less bitter.

Fruit + vegetables → macronutrient

  • Provides a range of vitamins and minerals which the body requires in small amounts

  • Body doesn’t store vitamin C

  • High in fibre.


1.Flour- pasta flour

2.Egg-”liquid needed” 

3.Olive oil-making the pasta glossy

>cooking pasta- becomes soft, weight x3 more than raw

>pasta machine- pushing pasta dough x5 per every width +folding it through the machine

>flavoured pasta-green pesto= spinach

Cooking of meat

nutrients meat provides: vitamin B3, B complex, magnesium, protein, zinc, potassium

why cooking meat: removes harmful bacteria, makes meat easier to swallow, chew    and digest, developing flavour, some meats cannot be eaten raw and steak tartare & carpaccio- raw meat 

when buying meat make sure:

-smells and looks fresh      -stored in good conditions

-clean shop                         -look at expiry date

storage of meat: below 5C- bacteria cannot reproduce as fast; well closed package because it contains CO2, keep closed, it could dry out, after freezed, use quickly chicken

commodity of using chicken

-low cost of raising chicken     -low fat       -high in protein

raw chicken

-bacteria associated with raw chicken- salmonella and campylobacter

-high risk food- should be stored under 5C (15-63C bacteria multiplies)

-use red board

prices of parts of chicken (per kg)

-whole chicken- 4. 50£    -thigh fillet- 5.76£                -chicken thighs- 3.00£.     -chicken drumsticks- 2.50£

-chicken legs- 3.50£        -chicken breast- 8.33£         -chicken wings- 2.19£

purpose of marinades

-tenderise the meat      -adds flavour to the food

-add moisture               -makes meat  nicer, attractive

cooking vegetables: Boiled, steer-fried, raw, in oven, soups, salads, casserole

storing vegetables, fresh, crunchy, bright colour, cool dry place, potatoes should be covered.

Victoria sponge: Creaming method

  • air as natural raising agent 

  • eggs help to set the air in place

  • baking powder: chemical raising agent (baking soda and sodium bicarbonate) when heated they will give off a gas (CO2)

  •  heat up the oven before to warm it up and the mixture will push up correctly

How do cakes cook

  • -hot air rises when we put them into the oven and the eggs set at 70C

  • A all ingredients together in bowl + 1 teaspoon baking powder

  • Self raising flour- gives structure

  • Soft marg- easier to whisk / makes it soft

  • Eggs- set the mixture in place

  • Caster sugar- makes the mixture sweet (for taste)

  • Baking powder- makes it big and fluffy

  • qualities of good cupcakes-: golden brown, fluffy, light

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