Transcript Investigation skills - Food a fact of life

Food Teacher Professional
Portfolio
Regional twilight events 2016/17
Programme:
5.00-5.20pm Registration
5.20 – 5.30pm Welcome
5.30 – 6.30pm Knowledge update
6.30 – 7.30pm Practical food investigations
7.30pm Finish
Starter activity – nutrition circle
map
1.
2.
In groups, write key facts that
students need to know about nutrition
in the outer circle.
Use the space in the rectangle to
identify how this can be taught along
with sources of information/where to
find resources.
Updating knowledge,
planning schemes of work
and resources is a
continuous process.
You will find a wide range
of support and advice to
help you.
Understand
curriculum
and
specifications
Review
own/
student’s
knowledge
Plan
effective
lessons
Source
reliable
information
NC2014
and new
GCSE
Update
own
knowledge
Key Stage 3 National Curriculum
and GCSE specifications
http://bit.ly/1IgkerU
http://bit.ly/2cCgQ5Z
http://bit.ly/2cL06de
http://bit.ly/2cj8rUq
Reliable sources of information
The BNF main website
provides nutrition information for teachers,
health professionals, scientists, and the
general public.
The healthy living pages provide general
health information whereas the nutrition
science pages are more in depth. The
Facts behind the headlines section would
be a great source of information to
challenge and extend pupils’ learning.
www.nutrition.org.uk
Food – a fact of life
Food - a fact of life provides a wealth of
free resources about healthy eating,
cooking, food and farming for children
and young people aged 3 to 18 years.
The resources are progressive,
stimulate learning and support the
curriculum throughout the UK. All
resources are designed to ensure that
consistent and up-to-date messages
are delivered.
Sign up to the newsletter online.
www.foodafactoflife.org.uk
BNF online training
• Brand new portal, modern
design.
• Responsive, so training can
be access via smart phones,
tablets and PCs.
• Easy to search for courses.
• Personalised courses
available.
• Training is accessed at:
nutrition.training
BNF courses
The following courses are online now:
• Catering for health
• Complementary feeding and obesity
• The science of dietary fibre and digestive
health
• Allergies – reducing the risk in early life
• Food labelling and health claims.
Coming soon:
• Introduction to healthy eating
• Exploring nutrition and health
• Teaching practical food lessons in primary
schools
Government sources of information
Government sources of information
Role
Scientific Advisory Committee on Nutrition
(SACN)
http://bit.ly/1OazV8C
SACN replaced the Committee on Medical Aspects of Food and Nutrition Policy
(COMA)
SACN members are appointed as independent scientific experts. SACN provides
advice to UK Health Departments on matters relating to food, diet and health.
Public Health England (PHE)
http://bit.ly/19WWAGu
An executive agency of the Department of Health in the UK.
Food Standards Agency (FSA)
http://www.food.gov.uk/
Responsible for food safety and food hygiene across the UK.
National Diet and Nutrition Survey (NDNS)
http://bit.ly/2cezhwt
Assesses the diet, nutrient intake and nutritional status of the general population
aged 1.5 years and over living in the UK. This is the only source of high quality
nationally representative data on the types and quantities of foods consumed by
individuals, from which estimates of nutrient intake for the population are derived.
Family Food Statistics
http://bit.ly/1NrKZAY
Family Food is an annual publication. It is a source of detailed statistical
information on purchased quantities, expenditure and nutrient intakes derived from
both household and eating out food and drink.
Overweight and obesity in school
children
One in five children aged 4-5 years in England
are overweight or obese
One in three children aged 10-11 years in England
are overweight or obese
Data source: National Child Measurement
Programme 2015/16
Overweight and obesity in adults
More than 4 out of 10 men in England are overweight
(41%)
27% of adults
are obese with
a Body Mass
Index of 30 or
more
More than 3 out of 10 women in England are overweight
(31%)
Data source: Health
Survey for England 2015
How are we doing in the UK?
Recommendation
Progress vs. recommendation
Fruit and veg
X
2.8 per day for 11-18 year olds (at least 5)
8% achieved the recommendation
Oily fish
X
53g/week for adults aged 19- 64 years (at least 140g/week)
Sugars (NMES/’free’)
X
15.2% in 11-18 year olds (<5% energy)
12.84% average all age groups
Fat

34% energy average all age groups (35%)
Saturated fat
X
13.2% energy average all age groups (<11%)
Trans fat

0.5% energy average all age groups (below 2%)
Fibre
X
11.62g average all age groups (NSP) (new recommendation 30g/day)
(AOAC fibre equates to 23g NSP a day)
Red and processed meat
 and X
Women aged 19 to 64 years (47g) and 65 years and over (57g) met the
current recommendation (less than 70g per day) but men did not (84g
and 81g respectively)
Vitamins & minerals
 and X
Some groups have low intakes
Source: NDNS 2016 http://bit.ly/2cezhwt
Vitamins and minerals
• Low vitamin D status was present in all age groups. The
new advice from PHE is that adults and children over the age
of one should consider taking a daily supplement containing
10mcg of vitamin D, particularly during autumn and winter
http://bit.ly/29PKdl3
• 48% of girls and 27% of women had low iron intakes below
the lower reference nutrient intake (LRNI).
• Iron deficiency anaemia and low iron stores were evident in
5% of 11-18 year old girls and 3% of adult women.
• Mean intakes of calcium, zinc (and iodine for girls only) were
also below the reference nutrient intake (RNI) and about a fifth
of girls aged 11 to 18 years fell below the LRNI.
• Mean intakes of potassium, magnesium and selenium were
below the RNI in all groups except children under 11 years
and substantial proportions fell below the LRNI.
The LRNI is the amount of a nutrient that is enough for only a small
number of people in a group who have low requirements (2.5%) i.e.
the majority need more.
Source: NDNS 2016 http://bit.ly/2cezhwt
The SACN report on Carbohydrates and Health
Sugar
Headlines based on evidence reviewed in SACN
report:
• higher consumption of sugars and sugars containing
food is associated with a greater risk of tooth
decay;
• increasing or decreasing total energy (calorie)
intake from sugars leads to a corresponding
increase or decrease in energy intake;
• consumption of sugars-sweetened drinks* results in
greater weight gain and increases in BMI in
children and adolescents;
• greater consumption of sugars-sweetened drinks is
associated with increased risk of type 2 diabetes. http://bit.ly/1CGGi33
This led to the following recommendations:
• Average intake across the UK population of free
sugars should not exceed 5% of total dietary
energy intake for age groups from 2 years
upwards.
• The consumption of sugars-sweetened drinks
should be minimised in children and adults.
http://bit.ly/1XfxSsq
Results from the NDNS Report of years 5
and 6 (combined) showed:
• The main sources of NMES in children
aged 18 years and under were ‘cereal
and cereal products’ (mainly cakes and
biscuits), ‘non-alcoholic beverages’
(soft drinks and fruit juice), ‘sugar,
preserves and confectionery’ and (in
younger children) ‘milk and milk
products’ (sweetened yogurt, fromage
frais and other dairy desserts).
Source: NDNS 2016 http://bit.ly/2cezhwt
What are free sugars?
All sugars added to foods by the
manufacturer, cook or consumer, plus
sugars naturally present in honey, syrups
and unsweetened fruit juice.
What sugars do not count as free
sugar?
Lactose (the sugar in milk) when naturally
present in milk and milk products and the
sugars contained within the cellular structure
of foods (e.g. fruit and vegetables).
In the classroom:
Free sugars line up
activity:
Link: http://bit.ly/1jPvtwu
Sugars resource
http://bit.ly/1XfxSsq
Fibre
•SACN also recommended an increase in the
population’s fibre intake to an average of 30g
AOAC* per day for adults (equivalent of 24g
NSP).
•For children, the recommended intakes are:
15g/day (age 2-5); 20g/day (age 5-11); 25g/day
(age 11- 16); 30g/day (age 16-18).
•The previous recommendation was equivalent to
23-24g/day AOAC fibre (18g NSP).
Why do we need to increase our fibre intake?
Evidence from the SACN report indicated:
•diets rich in fibre (cereal fibre and wholegrains) are
associated with lower incidence of CVD, type 2
diabetes & colorectal cancer
•diets rich in fibre decrease intestinal transit times
and increase faecal mass.
*(AOAC) is a method of
food analysis and is the
currently accepted
method for determining
dietary fibre in the UK,
continental Europe and
the United States.
AOAC amounts include
lignin and resistant
starches as well as
NSP.
To convert NSP to
AOAC (estimated)
multiply by 1.33.
In the classroom:
Fibre line up
Link:
http://bit.ly/1jPvtwu
The Eatwell Guide
In light of new evidence about our diet
and health, particularly revised
recommendations on sugars and fibre
made by the SACN report, a review of
The Eatwell plate was undertaken.
As a result of the review, a new healthy
eating guide for the UK has been
developed by the government– the
Eatwell Guide.
Then
Now
In the classroom:
CommNet FAB Toolkit –
healthy eating PPT which
also takes a look at healthy
eating models around the
EU Member States:
Link: http://bit.ly/1VrId3w
Fruit juice is now included in the
hydration message (not illustrated
pictorially in this group) but a
maximum of 150ml still counts as
one portion of 5 A DAY.
The purple segment now only
contains unsaturated oils and
fat spreads, which eaten in
small amounts, provide the
types of fat that are essential.
The name of this food group has
changed, to place emphasis on
plant sources of protein, such as
beans and pulses, that can be
considered environmentally
sustainable.
In the classroom:
What’s changed?
What is 150ml?
What’s changed?
Average energy requirements for men
and women have been added to
reinforce the message that all foods
and drinks consumed contribute to
total energy intake.
The segment sizes of
the food groups have
been adjusted to
reflect current
government advice
for a healthy,
balanced diet, such
as eating plenty of
fruit and vegetables
and higher fibre
starchy carbohydrate
foods.
Whole diet approach - why does Energy Density matter?
People tend to consume a relatively constant weight of food.
 energy density, potential to  energy intake, and volume of food
increases, increasing the opportunity to deliver essential nutrients.
Two strategies for eating 1575 kcal during a day
Food ED = 2.3
Food ED = 0.52
Energy density = no
of calories/weight
(grams)
For more information go to: http://bit.ly/2d4NhHW
The lower the ED, the bigger the portion (Rolls 2009)
Nutrition knowledge
Cooking knowledge
Cooking skills
Plan … (for need, person, context)
Make choices, based on evidence, knowledge & skills …
Justify decisions …
Core Competences
Food competences set out a progressive framework to help
children and young people develop the skills and knowledge to
make and implement healthy food and activity choices. There are
five themes:





diet and health;
consumer awareness;
cooking;
food safety;
active lifestyles.
http://bit.ly/1lAd4cA
The competences can be used as an audit tool to help plan
lessons; to support curriculum and qualification development, and
as a guide when developing resources.
Macronutrients
Carbohydrates
Practical activity and recipe
selection
Key knowledge
Key learning points
Recipe ideas
Source
 Two types of carbohydrate providing dietary energy—
starch and sugar
 Dietary fibre is also a type of
carbohydrate
 Non-starch polysaccharides
 Dextrinization
 Caramelisation
 Gelatinisation
 Scones/scone based pizza
 Lasagne (roux sauce)
 Macaroni cheese
 Potato and rosemary loaf
 Couscous
 Tuna and broccoli pasta
 Swiss roll
All starchy foods, such as bread, rice, potatoes, pasta, cereals and cereal products; fruit and starchy vegetables,
milk and milk products, sugar, preserves and
confectionery.
Function in the body
Provides energy for the body.
Protein
 Denaturation—mechanical and enzymic
 Foam formation
 Gluten formation
 Acid denature
 Coagulation
 Gelation
Source
Meat, fish, eggs, dairy foods, cereal products such as bread, soya products, nuts and pulses.
Function in the body
Do your recipes support knowledge, skill
development and progression AND reflect
the key nutrition messages?
Provides amino acids (building blocks) that we can’t make ourselves. Needed for growth, development and repair
of the body. Also provides energy.
 Bread
 Sponge cake
 Quiche
 Tandoori chicken
 Spicy bean burgers
 Meringue
 Fruit jelly
 Choux pastry
Fat
 Saturated and unsaturated
 Shortening
 Plasticity
Fats and oils, meat and meat products, dairy foods, oily fish, nuts, cakes, biscuits, pastry products, crisps and other
 Aeration
snacks, chocolate.
 Flakiness
Function in the body
 Emulsification
Source
 Marvellous mackerel pate
 Cheese and onion triangles
 Marble tray bake
 Cheese straws
 Pastry—short and rough puff
 Creaming method/all in one
 Granola bars/flapjacks
Provides essential fatty acids (that we can’t make ourselves but need in small amounts), as well as energy. It also
carries important fat-soluble vitamins and is important for their absorption.
Micronutrients
B vitamins, e.g. thiamin, riboflavin, niacin, B6, B12
 Water soluble vitamin
 Many types of vitamin B within this group
Source
Wholegrains, milk and milk products, egg, meat, poultry, white fish.
1.
2.
3.
4.
5.
6.
Base your meals on starchy foods
Eat lots of fruit and vegetables
Eat more fish
Cut down on saturated fats and sugar
Try to eat less salt
Get active and try to be a healthy
weight
7. Don’t get thirsty
8. Don’t skip breakfast
 Pitta pockets
 Moroccan lamb kebabs
 Lemon and herb coley goujons
 Omelette
Function in the body
Help to release energy from food. Helps with the function of the nervous system, and the maintenance of healthy
skin.
Vitamin C
 Water soluble vitamin
 Enzymic browning
 Knife skills
 Aids the absorption of iron
 Oxidisation
Source
Fruit especially citrus fruits and berries; green vegetables, peppers and tomatoes. Also found in potatoes.
 Vegetable kebabs
 Chunky vegetable soup
 Fruit salad kebabs
 Fruit fusion
 Potato curry
Function in the body
Acts as an antioxidant and is important for the normal structure and functioning of body tissues. It also helps the
body to absorb iron from non-meat sources such as vegetables, as well as assisting the healing process.
Calcium
Source
Milk and milk products, cheese and other dairy products, some green leafy
vegetables such as broccoli,
fortified soya bean products, canned fish (if containing bones that are soft and can be consumed) and bread.
 Absorption promoted by vitamin D
 Absorption inhibited by phytates (wholegrain cereals,
pulses) and oxalates (spinach,
rhubarb,
beetroot)
 Halloumi kebabs
 Macaroni cheese
 Greek yoghurt with honey
 Fruit smoothie
 Salmon paté
 Haem and non-haem iron
 Absorption of haem and non haem promoted by
vitamin C
 Absorption of non-haem iron
reduced/inhibited by
phytates, fibre, tannins (in tea)
and calcium
 Iron deficiency anaemia
 Spaghetti bolognaise
 Mini cheese and vegetable frittatas
 Salmon fish fingers
 Red lentil bake
Function in the body
Important for the formation and maintenance of strong bones and teeth, as well as the functioning of nerves and
muscles. It is also involved in blood clotting.
Iron
Source
Liver, red meat, pulses, nuts, eggs, dried fruits, poultry, fish, whole grains and dark green leafy vegetables.
Function in the body
Required for making red blood cells, which transport oxygen around the body. Also needed for normal metabolism
and the functioning of enzymes that remove unwanted substances from the body.
http://bit.ly/1jPvtwu
KS3 and GCSE planning
sheets
http://bit.ly/1jPvtwu
The Eatwell Guide
Resources include a presentation, a recipe
modification sheet, menu planners, a 'blank'
Eatwell Guide and food cards (for a sorting
activity): Link: http://bit.ly/1V6iRHY
New Eatwell Guide videos
Link: http://bit.ly/2cxIHla
New podcast – making better choices with the
Eatwell Guide Link: http://bit.ly/2cQkDg8
Eatwell classroom activities
Foods high in fat, salt and sugars
Compare the nutritional content of a
standard and a ‘reduced’ product.
Explain how the manufacturer has
modified the ingredients to achieve
the reduction in energy, fat, free
sugars or salt.
Fruit and vegetables
What is 30g of dried fruit?
Hydration
Hydration station –
provide fruit and
vegetables for students
to add to water to
encourage fluid
consumption.
Dairy and alternatives
Rank the following cheeses in order of fat content per 100g:
Mozzarella
Cottage cheese
Gouda
Danish Blue
Feta
Edam
Camembert
Goat’s milk cheese
Stilton
Half fat Cheddar
Cream cheese
Parmesan
Cheddar
Brie
grams of fat per 100g of cheese
50
40
30
20
10
0
Explore Food nutritional analysis programme - now updated
http://bit.ly/2bmdc0o
Applying knowledge
Eating more fruit and vegetables,
increasing the fibre content and
reducing the fat and free sugars
content of recipes is one strategy to
improving health.
Use these activities to help students
demonstrate how and why this can
be done using a variety of recipe
ideas.
Food route
Food route: a journey through food is a range
of colourful age-appropriate resources
designed and developed to enable young
people to gain food and active lifestyle
related skills and knowledge. Based on the
Core Competences, the resources cover:
•
•
•
•
•
Diet and health;
Shopping;
Cooking;
Food safety;
Active lifestyles.
http://bit.ly/1I8kjnI
Food route – up to the age of 14 years and 16+
Now updated to reflect The Eatwell Guide
http://bit.ly/1I8kjnI
Other active learning tasks
Activities in groups:
• How to teach nutrition theory relating
to water soluble vitamins
• Macro and micro nutrient treasure hunt
• Hydration – make an infusion
• Awareness of portion sizes – breakfast
cereals
• Portion size problems
Link: http://bit.ly/1jPvtwu
• Estimated and weighed worksheet
• Different cereal types – estimated and
weighed
• Bowl size impact
Link: http://bit.ly/1T6dUvo
Thinking maps linked to health
issues:
•
•
•
•
•
•
•
•
Bone health circle map
CVD brace map
Dental health circle map
Diabetes Venn diagram
Iron deficiency anaemia multi-flow map
Obesity mind map
Portion size problems – front of pack labels
Portion size problems worksheet
Link: http://bit.ly/1KVxNm3
Further information
Public health England:
• Summary of government’s energy and nutrient
recommendations: http://bit.ly/2bfT8bU
• Childhood Obesity A Plan for Action: http://bit.ly/2bpeBTp
• NDNS Years 5&6 combined (2012/2013-2013/2014) of
Rolling Programme: http://bit.ly/2aIL6bn
• Advice on achieving new vitamin D recommendations:
http://bit.ly/2aekuRe
• Getting every adult active every day: http://bit.ly/2a4FStR
• SACN report on Vitamin D and Health: http://bit.ly/2acOT5x
Food Standards Agency:
• Review of advice to consumers on raw or lightly cooked
eggs: http://bit.ly/2ajD0WA
• Campylobacter survey: http://bit.ly/2b1xtcP
Meat and Education
The website provides a range of teaching resources, suitable
for pupils aged 11 to 18, including:
• New support area for the Food preparation and nutrition
GCSE http://bit.ly/1d3shAi and specification grids with
links: http://bit.ly/2cW3ssB
• Six new red meat practical skills videos linked to the new
GCSE
• Lesson ideas, with curriculum links including the new 50
Minute lesson packs
• Recipes
• Interactive resources including Sausage Creator and
Gourmet Burger Builder
• Posters and photographs
• Bi-monthly eNews and printed resource – sign up online.
My Cooking Counts
• Website tool
Pupils
• Record own recipes (and photos)
• Assess their own food skills
• Know the main ingredients they use
• Certificate of achievement
Teacher
• Share recipes (ours, own & pupils)
• Track and monitor pupils cooking
achievement and repertoire
• Reporting
To register, go to:
www.meatandeducation.com
FTC resource bank – all the resources uploaded to the
FTC Facebook group organised and in one place!
Reviewing knowledge!
Activity - in groups of 4 you have 60
seconds to write down everything you know
about:
•
•
•
•
•
•
•
Carbohydrate
Protein
Fat
Vitamins
Minerals
Fibre
Water and hydration
Choose a scribe and then a speaker!
Updating knowledge, planning
schemes of work and resources
is a continuous process.
You will find a wide range of
support and advice to help you.
www.foodafactoflife.org.uk
www.nutrition.org.uk
www.foodteacher.org.uk
www.foodteacherscentre.co.uk
Food Investigations session:
• Caramelising onions
• Enzymic browning
• Emulsions in butter
• Glazing pastry
Can you describe a raw onion?
The science behind browning onions
Onion chemistry
The enzyme in onions is called allinase
which:
• makes your eyes water
• becomes active when cells are cut open.
If you boil onions or heat them the enzymes
are destroyed.
Onions have large cells containing water.
Q What else can you find out about
onions?
Caramelisation of onions
Investigation: caramelisation of onions
Equipment
Weighing scales
Chopping board
Vegetable knife
Teaspoon
Frying pan
Spatula for stirring
Matching bowls for
serving
Food probe
Ingredients
Brown onion
Ghee or oil
Caster sugar
Sodium bicarbonate
Investigation: caramelisation of onions
•
•
•
•
Onions are naturally sweet.
Slow cooking breaks down the natural sugars in the onions
and they become sweeter.
Caramelisation occurs as a result of the simple cooking of
sugar.
In many recipes the onions are initially sweetened by
caramelisation to improve flavour and colour in the dish.
Additional task – research kilocalories and carbohydrates in the
onion family
Investigation: caramelisation of onions
Method:
1. Weigh the onion then remove skin and reweigh.
2. Peel and slice onion into measured slices.
3. Weigh sliced onions.
4. Melt ghee or oil and fry gently – time
caramelisation.
5. Use food probe to check temperatures as onions
caramelise.
6. Compare to sugar boiling scales.
7. Test pH of mixture.
Variables:
• Onions
and ghee
• Onions,
ghee and
10g
caster
sugar
• Onions,
ghee and
10ml
balsamic
vinegar
Investigation: caramelisation of onions
Additional variables to try:
• Add ½ tsp teaspoon bicarbonate soda – makes the pH more
alkaline and speeds up browning
• Soak the sliced onions in water, drain, dry and fry
• Use different frying fats: rapeseed oil, olive oil, dripping
• Add 10g of plain flour, or cornflour to the onions
• Add 10g apple juice or 1 tsp caster sugar
•
Vary the onions – red onion, shallots, leeks.
Data to collect:
•
•
•
•
•
•
•
Weight of raw onion
Weight of onion pre cooking
Weight of onion caramelised
Comparison of colour of onions against a benchmark range
(photograph)
Accurate small measurements of 10g sugar etc
Sensory analysis – raw / caramelised onions
Recipes that incorporate caramelisation of onion.
.
Science of caramelisation
•
•
Evaporation / softening / enzyme destruction.
Caramelisation/sweetening/Maillard reaction.
Benchmark of onion colourations as they brown.
White / speckled brown/ golden /dark golden / rich dark golden / rich brown
5 scientific stages when onions are browned
1
Evaporation
• When onions are heated the first thing that happens is
that the water evaporates and steam is seen and heard it sizzles out of the onion cells. Around 75% of an onion
is formed from water.
• As the water is forced out the cellular structure of the
onion softens.
2
Enzymes
•
•
•
Allinase is the enzyme which causes irritation to our
eyes and makes us cry when chopping raw onions.
During cooking the temperature increases and the
enzyme is destroyed.
Other enzymes are released from the cells and mix
together.
3 Browning
•
•
•
Evaporation enables the temperature of the onions to
increase to 110⁰C.
Sugars oxidise and compounds are formed.
You begin to see the onion go brown.
4
Sweetening
• Sweetness increases as the sugars breakdown.
• Disaccharides turn to monosaccharides.
• Fructose is sweeter than sucrose therefore the onion
becomes sweeter in taste.
5. Maillard reaction
•
•
Maillard reactions occur when
proteins and carbohydrates
combine through heating.
Sugars, proteins and enzymes
work together to produce the
‘golden’ and sweeter attributes of
Maillard reactions.
Slow gentle cooking of onions is
key to optimal caramelisation and
flavour development.
French Onion Soup
Method:
1. Caramelise onions
2. Add to rich beef stock
3. Thicken very slightly with potato starch or
cornflour
4. Check seasoning
5. Add French bread slices
6. Add grated Gruyère cheese
7. Grill and serve.
Investigation: enzymic browning
•
•
•
•
Use an apple or parsnip.
Use a cutter or good knife skills to portion
it.
Make 8 slices.
Photo the 8 portions.
Investigation: enzymic browning
Variables:
• 1 control
• 2 close wrap in cling film
• 3 immerse in cold water
• 4 immerse in brine ( salt and water solution)
• 5 immerse in lemon juice
• 6 immerse in bicarbonate of soda
• 7 immerse in caster sugar
• 8 immerse in vitamin C solution.
Activity using apple, parsnip or aubergine
•
•
•
Photo slices.
Photo again after 10 minutes.
Photo after 20 minutes.
Questions to ask:
•
•
•
•
What do you see?
Why has this happened?
What conditions would prevent the changes?
Design an investigation to explore this.
Enzyme action
Investigation skills
•
•
•
•
•
•
•
Accurate slicing – knife skills.
Organisation: equipment / timing / layout.
Research skills: enzymes and how they work.
Research on pH and its effect on enzymes.
Recipes where browning would adversely affect the product.
Ability to write up experiment.
Handling results / data.
Investigation: glazes on pastry
•
•
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Roll out pastry with formers to ensure a standard thickness.
Cut into strips and divide strips into 3.
Keep 1 raw square portion.
Use glazes – brushed over the raw pastry.
Investigation: glazes on pastry
Variables:
• Control not glazed
• Egg wash
• Egg white with pinch salt
• Egg yolk
• Sugar solution
• Milk semi skimmed
• apple juice
• honey .
Ideas for glazes – class trials
I’ve got an
idea – can
we try
cocoa?
Cooked samples for discussions
Egg wash
Yolk wash
Sprinkled sugar
Soy sauce
Tomato ketchup
Grainy mustard
English mustard
Cheese
Salt
Honey
Apricot glaze
Flour sprinkle
Milk
Investigation skills
Research:
• Glazes in use in cooking / recipe
• Dextrinisation of starch by dry heat
• Caramelisation
• Maillard reaction.
Investigation skills/data collection
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Note colour.
Prepare a benchmark for colour of pastry.
Rank glazes - depth of colour, gloss.
Sensory analysis - flavour enhancement.
Investigation: Butter production
Using the equipment provided:
• Weigh the empty container
• Pour in 125ml double cream, weigh the cream
• Screw on lid
• Shake until you hear the butter has split.
• Drain.
• Weigh the butter produced.
• Press into moulds, chill.
Investigation: Butter production
Questions:
• Where does the butter come from?
• What is left behind when the butter has formed?
• How could you use this in your teaching?
What happens as butter is formed?
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Creaminess is a sensory factor, an emulsion of lots of tiny fat
globules suspended in a small amount of liquid.
Whipped cream is a foam, a suspension of gas bubbles
stabilized by its own fat.
As you whip cream air is trapped causing an increase in
volume.
Firmer peaks form that hold their shape.
What happens as butter is formed?
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On further whipping there is damage to the phospholipids
membrane, exposing even larger portions of fat.
Fatty friends clump together. The air is driven out and the
foam deflates.
Butter curds appear as little clumps which finally form a solid
portion.
Drain and knead or churn to remove excess liquid which
might enable microbes to get to work and sour the cream.
Chilled storage is required
Use as butter.
Irreversible reaction – butter will not turn back to cream.
Emulsions in butter and milk
Butter
Water in oil (fat) emulsion
Milk
Oil in water emulsion
The science of making butter
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Butter can be made in a food processor, using a hand mixer
or in a jar. The key is agitation.
Cream that is agitated (whisked) incorporates air and
becomes thicker.
Continued agitation causes the little globules of fat to
collide, damaging their walls and allowing the hydrophobic
(water-fearing) regions to clump together.
The science of making butter
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Fatty triglycerides gather into a mass of butter, separating
from the buttermilk (watery liquid).
Incorporated air is expelled, two phases remain - fat and
buttermilk.
Butter is 82% fat.
It is a water in oil emulsion.
Thank you!
For more information and resources,
go to:
www.foodafactoflife.org.uk
www.foodteacherscentre.co.uk
www.thecookeryteacher.com