Transcript GCSE Food Tech - Exam Section B File

GCSE Food Technology
- Section B of the Exam
Eat well plate
8 guidelines for a Healthy Diet
1. Base your meals on starchy foods, e.g. Potatoes,
rice, bread.
2. Eats lots of fruit and vegetables
3. Eat more fish
4. Cut down on saturated fat and sugar
5. Try to eat less salt – no more than 6g a day
6. Get active and try to be a healthy weight
7. Drink plenty of water
8. Don’t skip breakfast
Activity: List the illnesses that could be prevented
by following this advice.
Functions of nutrients
Nutrient
Job in the body
Sources
Carbohydrates
Energy
Sugar, honey, jam
Potatoes, rice, pasta
Fat
Protection/insulation
Some energy
Butter, cheese, oily fish,
meat
Protein
Growth and repair
Secondary energy source
Meat, fish, eggs, cheese,
lentils, beans, soya, nuts.
Vitamin A
Healthy skin and tissue
Helps vision
Liver, eggs, butter, yellow
and orange fruit & veg
Vitamin B
Transfer and release of energy
Formation of red blood cells
Cereals, meat, fish, dairy,
pulses, yeast products.
Vitamin C
Healthy skin and body – helps resist
infection. Absorption of iron
Fruit and vegetables
Vitamin D
Growth and maintenance of strong
bones. Absorption of calcium
Exposure to sunlight
Oily fish and eggs
Iron
Formation of red blood cells which carry
oxygen around the body.
Red meat, dark green veg,
Eggs, chocolate, dried fruit
Calcium
Keep bones and teeth strong
Healthy muscles and nerves
Dairy foods
White bread
Canned fish
Green leafy veg
Water
For all body actions
Removes waste
Drinking water, fruits,
milk
Dietary reference values (DRVs):
Scientifically calculated estimates of the amounts of nutrients needed by
different groups of people.
Activity:
Two DRVs commonly used are RNI and EAR use the internet to find out
what they refer to.
NSP – Non starch polysaccharide/dietary fibre is not a nutrient but is vital
for our bodies.
Explain why and which foods we get it from.
Traffic light labelling
Specific dietary groups
• Diabetics
• Coeliacs (require gluten free diet)
• Low fat / Low salt – to reduce the risk of coronary
heart disease (CHD) / stroke / high blood pressure /
obesity
• Vegetarian - eat only dairy animal products (milk,
eggs, cream etc.)
• Vegan – no animal products whatsoever
• Nut Allergy
• Lactose Intolerant (unable to have cow’s milk /
milk products)
• Calorie controlled
Activity: Match the logo with the dietary
requirement
Religious requirements
Understanding the role of food in cultural and religious
practice is an important part of showing respect and
responding to the needs of people from a range of religious
communities. However, it is important to avoid
assumptions about a person’s culture and beliefs.
Requirements
Catholic &
Orthodox
christian’s
Some Catholic and Orthodox Christians observe several feast and
fast days during the year. For example, they may fast or avoid
meat on Fridays, during Lent or on Good Friday. Some eat fish
instead.
Protestants
Most Protestants observe only Easter and Christmas as feast days
and don’t follow ritualised fasting.
Religion
Requirement
Muslim (Islam)
•Halal (foods prepared in certain way)
•Do not eat pork
•Do not drink alcohol
•Haram (products not allowed)
•Ramadan (month of fasting from dawn until dusk)
Hindu
•A large number of Hindu’s are vegetarian
•Do not eat Beef as the cow is sacred
•Some do not eat pork
•Some do not drink alcohol
•Fasting will depend on caste
Jewish (Judaism)
•Only eat Kosher meat
•Do not eat pork or shell fish
•Only eat the front quarter of the animal
•Will not eat meat and milk together (such as lasagne)
•Fasting - Yom Kippur (day of atonement) lasts from dawn
until dusk.
Buddhism
Some do not eat meat or meat products
Others only shun beef
Standard Components
• Standard components are pre-prepared ingredients used during
the manufacture of food products. They are made at a different
time, and often at a different place by another company. Common
examples are:
• Pre-shaped pastry (e.g. flan case /tart case for savoury flan / tartlet / mini
pasty / mini roll)
• Readymade pasta
• Ready mixes of ingredients (e.g. Cheese sauce, frosting/icing mixes)
• Breadcrumbs – for breaded mushrooms / prawns/ chicken goujons
• Toppings – grated cheese
• Pre-prepared fruit & vegetables (for salads – pasta prawn salad,
sandwiches, readymade dips)
• Batter mixes (e.g. For butterflied prawns, Yorkshire puddings)
• Readymade sponge flan cases / icings/ cake decorations e.g. Chocolate
curls
Advantages of standard components:
Using standard components helps ensure a consistent final product
because they are of a standard quality. For example:
• standard weight
• standard size (e.g. Tart case, pizza finger, bread roll)
• standard shape (e.g. pastry case) standard intensity of flavour (e.g.
stock cube)
• accurate in ratio (proportions) of ingredients (e.g. sauce mix /
pastry/ sponge mix)
• Standard components are often used to save time and money. They
also help quality control by guaranteeing a consistent and reliable
quality. A specialist supplier can often make them cheaply because
they can be manufactured in very large numbers on a dedicated
production line.
Advantages & Disadvantages of Standard Components
Advantages
Disadvantages
Manufacturers may use
standard components:
There are some disadvantages
to using standard components:
To save time
Can be more expensive
Because they do not have the
necessary specific machinery or
skilled workers
The manufacturer is relying on
another company that could let
them down
So that the quality is guaranteed
Time must be allowed for ordering
and supply
Because complex production lines
take up a lot of space and are
expensive to set up.
Components are usually bought in
bulk and have to be stored in the
right conditions
So that a wider range of products
can be produced
Hazards in food preparation
What are Hazards?
• Hazards are anything that can cause harm to the consumer. They can occur at
any stage in the food production chain from the field to factory to shop to
table.
• Biological:
• e.g. salmonella in raw chicken , seafood or eggs, Campylobacter
(gastroenteritis) found in seafood, meat, poultry & milk; Listeria in soft
cheeses and pates, E-coli in cooked meats, Clostridium botulium found in
canned fish, meat & vegetables.
• Chemical:
• e.g. cleaning chemicals, agricultural chemical, paint, oil
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Physical: e.g.
Glass from bottles, jars, light fixtures
Metal from machinery, equipment, packaging, jewellery
Wood from pallets, boxes
Insects from plants, open windows
Personal items e.g. jewellery, hair, fingernails, cigarettes
Packaging faults e.g. bags not sealed
Food spoilage
Bacteria, yeasts and moulds are the microorganisms that
cause food spoilage.
Bacteria need certain conditions to grow:
• Temperature - rapid growth at 37c (danger zone 5-63c)
• High risks foods (high amounts of protein and water.
• Time – they can divide in two every 10 -20 minutes meaning
in a few hours one bacterium can become several million...
• Moisture – foods contain moisture so are ideal for maximum
growth.
If we alter optimum conditions needed for bacteria growth it
will stop them from reproducing or greatly slow down the
rate of reproduction.
How do we help prevent bacteria growing in food?
Freezing - 18c bacteria are dormant and not able to reproduce
Chilling - 0-5c bacteria are sleeping and reproduce extremely
slowly
Storing – by not storing food in the danger zone 5-63c – where
bacteria produce most actively. Chill and store quickly.
Cooking – Ensure food is coked to the correct temperature – 75c
Bacteria starts to be destroyed after 72c
Activity: Discuss the 4c’s of food hygiene
The Danger Zone!
75c
• 75c – Temp of reheated
food.
• 72c – Temp at which food
must reach for at least 2
minutes.
• 5oC – 63oC – Danger Zone
• 0-5c – Fridge temp
• -18oC Freezer temp (+ or –
3oC)
72c
63c
-18c
Food contamination
What is ‘Food contamination’? Food contamination means:
• That food has micro-organisms/bacteria in it
• Food may cause food poisoning / unsafe food
• Food becomes harmful because of physical/chemical/biological
Contaminants
Cross contamination can be prevented by checking :
Staff (clean uniform / healthy / no visible cuts / boils etc.)
Sanitising & cleaning equipment / surfaces
Checking equipment is safe and in good condition
Use of colour coded chopping boards
Checking storage temperatures,
Rotation of stock (FIFO)
Activity: Write which food is for each colour
board
Temperature probe
Do not call
this a
thermomet
er in the
exam!
Activity:
Explain how and why you
would use a temperature
probe in food production.
Food storage
How does preservation help ensure a longer shelf life?
If we alter any of the optimum conditions needed for bacteria
growth it will stop them from reproducing or greatly slow it
down.
The main methods for preservation are:
Removal of liquid
Drying, dehydration, jamming
Alteration of temperature
Canning, freezing, chilling
Removal of air
Modified atmospheric packaging
Addition of preservative
Jamming, pickling, salting
Activity: State foods you know are preserved using these
methods
Food Additives
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They can preserve food for longer so it is easier to transport and sell products
Types of food additives:
• Preservatives
• Colourings e.g. tartrazine
• E numbers
• Flavourings
• Emulsifiers e.g. Lecithin (found in egg yolk)
• Natural
• Raising agents / baking powder
• Synthetic
• Stabilisers
• Anti oxidants
• Anti caking agents
• humectants
• Nutrient and flavour enhancers
improve flavour, texture and
appearance
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Sweeteners are better for the teeth and have less calories
Some antioxidants like vitamin C are good for your health
They can maintain or improve nutritional values
They increased the variety and quantity of food
Meets dietary needs (e.g. diabetics and sweeteners)
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They can preserve food for longer so it is easier to transport and sell products
They improve flavour, texture and
appearance
Sweeteners are better for the teeth and have less calories
Some antioxidants like vitamin C are good for your health
They can maintain or improve nutritional values
They increased the variety and quantity of food
Meets dietary needs (e.g. diabetics and sweeteners)
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They can preserve food for longer so it is easier to transport and sell products
They improve flavour, texture and
appearance
Sweeteners are better for the teeth and have less calories
Some antioxidants like vitamin C are good for your health
Advantages and disadvantages of food additives:
Advantages
• Natural additives – no ‘chemical’ content
• Enable food to be preserved
• Improved colour / flavour
• Improve sensory attributes of food
• Use out of season
• Longer shelf life
• Prevent separation of e.g. dressings
• Allow colour of product to be constant, e.g. jam
• Prevents oxidation of fats in baked products
Disadvantages
• Synthetic additives are created in a laboratory
• Safety of some additives a concern
• Make some foods look unnatural and artificial
• Additives need approval from the EU, e.g. some are
removed /
withdrawn
• Risk of hyper activity in children
May give examples e.g. colourings in squash
• Other health problems linked to the use of additives:
Increased asthma
Eczema
Food intolerances
• Unknown health risks of some additives
Modified starches
• Modified starch, also called starch derivatives, are prepared by physically,
enzymatically, or chemically treating native starch, thereby changing the
properties of the starch. Modified starches are used in practically all starch
applications, such as in food products as a thickening agent, stabilizer or
emulsifier.
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Pre-gelatinised
starch is used to thicken instsnt desserts without heat. A cold
liquid can be added and the dessert will thicken when stirred or whisked,
e.g. Instant whip, angel delight
Acids and alkalis
All foods are made up of a variety of natural food chemicals.
The type and amount of food chemicals present in the food
create the conditions:
• Acid
• Alkali
• Neutral
Acids and alkalis can influence changes the occur when some
ingredients are combined.
Uses of acids
Citric acid (lemon juice)
• Citric acid can be added to cut fruit to prevent enzymic
browning.
• To set (coagulate) some chilled desserts. The protein in cream
and milk sets when mixed with citric acid.
• To help jam set. The acid helps form a gel.
Acetic acid (vinegar)
• To tenderise tough meat. Marinating in a vinegar solution
tenderises the meat giving it a softer texture.
• Softens a meringue texture when added to meringue mix.
• To add flavour – salad dressing etc
• To preserve food e.g. Onions, beetroot, cabbage etc
Acid conditions prevent the growth of microorganisms
Ascorbic acid (vitamin c)
• Added during commercial bread production to speed up
fermentation process (release of carbon dioxide)
• Used in cheese production to coagulate milk
• Used to make raising agent – baking powder
Alkalis
• Used in raising agents such as bicarbonate of soda – they
produce carbon dioxide when heated.
• Produces cracked appearance on biscuits like ginger nuts due
to addition of bicarbonate of soda
Electrical Kitchen Equipment
Health and safety rules to be followed by food workers using electrical
equipment.
Hand
• •Keep away from water
Blender
• •Follow manufacturers instructions
• •Check condition of flexes
• •Check wiring on plug
• •Do not use with wet hands
• •Do not leave flexes across water supplies
Electric Whisk
• •Check equipment has passed safety checks e.g. PAT tests
• •Accept equipment specific responses, e.g. blender, mixers
• •Hold securely / securely based during use.
• •Keep fingers / clothing/ hair away from any moving parts
• •Have training in correct use of equipment
• •Equipment should be clean before/after use
• •Personal safety precautions/ Wear clean, protective clothing
• •Concentration during use/ do not leave unsupervised.
Tabletop Food Mixer
Equipment
Advantages
Disadvantages
•Grates, slices, chops
•Processes food quickly
•Blends liquids/foods
•Optional attachments
•Small processors available
•Safety features
•Can be expensive
•Needs storage space
•Difficult to clean?
•Mixes cakes, dough etc
•Different attachments
available
•Mixes large quantities
•Kneads dough
•Heavy
•Needs storage/worktop
space
•Expensive to buy
•Blends
•Purees
•Easily stored
•Cheap to buy
•Blades not covered
•Power supply needed
•Whisks eggs, cream, cake
batters.
•Hand held
•Limited mixture amount
•Mixers not protected
•Aerates mixtures
•Dough hooks mix bread
dough.
•Easily stored
•Cutters
•Consistent shape
•All same shape
•Can be expensive to buy
•Bakes at the correct
temperature
•Makes set amount
•Even size
•Good quality
•One shape only
•Set amount made
•May need specific recipe
Sensory Testing
Food manufacturers use sensory testing when they are creating or improving food products.
Testing is always carried out in controlled conditions. This refers to having all conditions the
same, so it is unbiased /has no way of influencing tester / neutral conditions. Examples are:
• So useful comparisons can be made between samples
• Same size samples
• Identical dishes
• Identical quantities of food
• Coded samples
• Same light conditions
• Noise free area
• Smell free area
• Individual booths for privacy
• Blind testing/blindfolded
• Clarity of instructions given to taste
• Water/cracker to refresh mouth after each tasting
• Similar charts used to record outcomes
Quality control checks using
computers
Types of control checks:
• Timing
• Temperatures of oven
• Metal detection
• Weigh of ingredients
• Quality Control, e.g. shape, size
• Portion control
• Microbiological checks
• Other relevant checks
Why Computers are used:
• More accurate than humans in
minute measurements
• Less staff needed / cost reduction
in long term
• Humans may be unable to carry
out the check
• Safety
• Speed / quicker / saves time/
reliability
• Ability to record results / store results
• Automatic, 24 hours a day
• Other relevant reasons
Advantages and disadvantages of using
computers to carry out market research.
Advantages:
• Less human error / more reliable / quicker
• Cheaper than employing extra staff to research / in long term
• Greater accuracy and up to date information
• Wider range of information available
• More consistent
• Easier to carry out analysis of statistics / results
• Can be carried out when human not present,
• Clearly presented results e.g. graphs, charts
• Can make changes easily to update current data
• Results can be analysed quickly, e.g. on Excel
• Easier to import other programs and
software.
Disadvantages
May be expensive to set up initially / decreasing profits
• Need to decide on validity of entries on websites or other information used
otherwise results are
worthless
• Need to train staff in it use or inaccuracies will result
• If information is inaccurate it can affect success of future products based on
research
• Lack of human interaction may lead to incorrect results
• Lack of compatibility between software programs
• Difficulties/costly if system breaks down, need back up.
Food Labelling
Compulsory:
By law, all food manufacturers
(people who make food
products) must have the
following on their food labels:
• Name of product
• Description of product
• Manufacturer’s name & address
• Weight or volume
• Storage instructions
• Cooking or preparation
instructions (e.g. heating up
ready meals)
• List of ingredients (heaviest
first)
• ‘Best before’ / ‘Use by’ date
Optional Food Labelling:
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Food Manufacturers will often add one or more from the list below, although
these are not required by law:
• Illustration (picture / photo)
• Bar code or smart code – they identify the price and are used by shops
and manufacturers for stock control.
• Special claim (e.g. ‘low fat’)
• Symbol for average quantity (e)
• Nutritional information of the product. If the special claim is about a
nutrient, this information MUST be included.
• Customer guarantee
• Price – although lots don’t as they have smart codes.
• Allergy advice
• Recycling logos and anti-litter symbols to encourage consumers to recycle.
• Serving suggestions e.g. serve with custard or cream.
The purpose of packaging
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Protection - Packaging protects foods from:
Physical damage during transportation and storage
The effects of temperature changes, insect or rodent attacks, mould growth etc.
Packaging guarantees food safety and hygiene.
Containing – Packaging contains the contents:
so that they can be transported, stored and displayed easily.
Packaging can make awkwardly shaped products easy to handle.
Preserving –
Packaging can be part of the preservation process such as tin cans and modified
atmosphere packaging (MAP) (see below).
Identification –
Packaging describes and identifies the contents.
Good packaging design gives a brand image and links other products in the range.
Orange, yellow and blue are popular packaging colours.
Preventing Tampering –
Packaging helps stop the tampering of goods. It’s almost impossible to make
packaging tamperproof, but it can be designed so that it’s obvious if the package
has been opened.
Packaging issues
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Excess use leads to poor environmental control / deforestation /world’s
natural resources (e.g. oils) running out
Use of recyclable packaging/biodegradable/concern over length of time
to decompose
Ethical/ environmental /moral concerns/issues.
No use of packaging if preferable but need to package certain foods and
for cooking
Storage problems for foods and left over packaging
Queries over information provided on packages e.g. Nutritional labelling
Chemicals used in some food packaging
Impact/harm of wildlife
New technologies – vacuum packaging nanotechnology/ coatings, MAP,
aseptic (e.g. TetraPak) – benefits and advantages.
Food miles
Is the distance food travels from where its produced to where
it’s sold.
Facts and figures
•UK food exports in 1994 - 12 million tonnes. UK food imports in 1994 - 20 million
tonnes.
•Each tonne of food travelled an average of 123 km in 1998 (the average figure was 82
km in 1978)
•Food in the UK now travels 50% further than it did 15 years ago.
•Five large retail chains account for 80% of food sold in the UK.
•Transportation of food was responsible for 33% of the increase in road freight over
the last 15 years.
•In the UK, road transport is the only source of a greenhouse gas (carbon dioxide) that
is still increasing.
What can we do about this?
Buy locally sourced ingredients and eat in season. Try to avoid
buying ingredients that have travelled long distances.
What is sustainability
By purchasing local foods in-season, you eliminate the
environmental damage caused by shipping foods thousands of
miles, your food pound goes directly to the farmer, and your
family will be able to enjoy the health benefits of eating fresh,
unprocessed fruits and vegetables. Foods that are in season are
better in terms of nutritional value and are cheaper. Buying
seasonal produce also provides an exciting opportunity to try new
foods and to experiment with seasonal recipes. It simply tastes
better too!
Activity: Analyse the table and explain why consumers
buying more locally sourced/free range/organic/farm
assured products helps sustainability.
Ethical food choices
Free range:
A term which denotes a method of farming husbandry where the animals
can roam freely for food, rather than being confined in an enclosure. On
many farms, the outdoors ranging area is fenced, thereby technically
making this an enclosure, however, free range systems usually offer the
opportunity for extensive locomotion and sunlight prevented by indoor
housing systems.
Organic:
Grown, reared, produced without the use of chemicals, fertilisers or
pesticides.
Free range and organic may apply to:
• meat
• eggs
• fruit and vegetables
• dairy farming
The Red Tractor Farm assurance:
A food assurance scheme which covers production standards
developed by experts on safety, hygiene, animal welfare and the
environment amongst other things.
Soil association:
Our definition of organic food is food which is produced using
environmentally and animal friendly farming methods on organic
farms. These methods are legally defined and any food sold as
'organic' must be strictly regulated. Organic farming recognises the
direct connection between our health and how the food we eat is
produced. Artificial fertilisers are banned and farmers develop fertile
soil by rotating crops and using compost, manure and clover.
Fair Trade:
Fair trade foods ensure that the workers or Farmers who produce the
foods get a fair price for their produce and have a reasonable standard
of living. Fair trade is about guaranteed fair prices for the farmers,
farmer workers and their families, better working conditions and local
sustainability. Companies who buy the farmers’ products must pay the
market price. Fair trade foods include coffee, tea, chocolate, icing sugar,
caster sugar and bananas.
Genetically Modified foods
Foods that scientists have altered the genes within food to
give it other characteristics. Combining or adding genes form
one food to another achieves this. The characteristics
achieved can:
• Make crops resistant to disease
• Increase the nutritional quality of food
• Increase the quantity of the food grown from the same
amount of land seeds.
Scientists feel that genetic engineering could lead to side
effects in other foods grown near GM foods. More research is
needed.
Nano foods
All products are made from ATOMS. These are between 1 and
100 nanometres (nm) in size.
One millionth of a millimetre...
If we rearrange these atoms we can change the food product
completely.
We could:
• Reduce salt, sugar and fat but retain the flavour.
• Change the look/appearance/size/shape
• As with GM foods more research needs to be done before we
can assess possible side effects.