Transcript Slide 1

From field to fork:
the potato’s journey
There are many varieties of potato, each with a different taste and texture. Potatoes can be
divided into two different kinds, either waxy or floury. The term ‘waxy’ usually refers to a young
potato, while ‘floury’ is an older potato containing less moisture.
Q
Where were potatoes first discovered?
A
The Potato has been around for about 6,000 years, and was first cultivated by the
Inca Indians in Peru. The Peruvian Quechua language records more than one
thousand words to describe potatoes and potato varieties.
Centuries later, the invading Spanish conquistadors had been on the look out for
gold and jewels - potatoes became one of the exotic finds they brought back to
Europe to impress royalty in 1536.
(Key Stage 1: History 4a
Key Stage 2: History 4a b)
Q
Which of the following European countries: Italy, UK, Ireland, France, Germany,
Portugal, consumes the most potatoes each year?
A
Portugal! (Ireland is the second highest consumer with the UK third).
(Key Stage 1: Geography 1a b
Key Stage 2: Geography 1a b)
Small Group Work
Key Question
(15 – 20 mins)
What varieties of potato are there and what can you do with them?
Activity 1
Can you work out which of the following names are varieties of potato and which are types of
bread?
Place a 4 against those names you think are varieties of potato and a 8 against those that
you don’t think are potatoes.
How many did you answer correctly?
(Key Stage 1: Design & Technology 4a 5a Key Stage 2: Design & Technology 4a 5a)
Name
4 or 8
Name
Maris Piper
Stottie
King Edward
Bannock
Bara Brith
Nadine
Desiree
Estima
Muffin
Sally Lunn
Huffkin
Coburg
Saxon
Wilja
4 or 8
Activity 2
(30 – 45 mins)
How do you like to eat your potatoes? See if you can work out which potatoes are best
suited for either: boiling and mashing, roasting, baking, chipping, salads, or for
general use.
If you think the potato variety Wilja is best suited to roasting, place a 4 in the box next to
the name or, if you think it tastes better as a salad potato, place a 4 in the box.
You might think that some potatoes can be used for more than one type of cooking, but
we are just trying to find out which potato variety you think is best for each type of
cooking.
The first one is done for you!
(Key Stage 1: Science Sc1: 2a b
Key Stage 2: Science 2a)
Variety
Maris Piper
Saxon
Wilja
Cara
Nicola
King Edward
Nadine
Romano
Marfona
Charlotte
Desiree
Estima
Sante
Maris Peer
Boil
Roast
Bake
Chip
Salad
General
4
Activity 1
Name
4 or 8
Name
4 or 8
Maris Piper
4
Stottie
8
King Edward
4
Bannock
8
Bara Brith
8
Nadine
4
Desiree
4
Estima
4
Muffin
8
Sally Lunn
8
Huffkin
8
Coburg
8
Saxon
4
Wilja
4
Activity 2
Variety
Boil
Roast
Bake
Maris Piper
Saxon
Chip
Salad
4
4
Wilja
4
Cara
4
Nicola
4
King Edward
Nadine
Romano
Marfona
4
4
4
4
Charlotte
4
Desiree
4
Estima
Sante
Maris Peer
General
4
4
After cultivation a destoner is used to remove stones from the seedbeds and create
beds of soil into which the potatoes are planted. As stones and potatoes are often
about the same size it is important to remove them from the seedbed.
Q
What do you think the machine in the picture is called?
A
Destoner
(Key Stage 1: Science: Sc1, 2a. Key Stage 2: Science: Sc1 1a, 1b. 2a, 2b).
Q
Why is it important to remove stones from the soil?
A
To improve the growing conditions for the seed potato. Too many stones would
restrict the growth of the tubers. b. When harvesting, because some of the
stones would be a similar size to the potato, the harvester would ‘collect’ stones
as well as potatoes. This would require more labour to sort the potatoes from the
stones.
(Key Stage 1: Science: Sc1, 2a, b, c. Sc2 3a. Key Stage 2: Science: Sc1 1a, 1b. 2a, 2b, 2c).
Q
What do you think would happen to the field if all of the stones were removed?
A
Removing too many stones would reduce drainage and cause waterlogging and
potential destruction of the crop.
(Key Stage 1: Science: Sc1 1, 2a, 2b, 2c. Geography: 1a. 2a. 4b.
Key Stage 2: Science: Sc1 1a, 1b. 2a, 2b, 2c. Geography: 1a, 1c. 2a. 3d. 5a, 5b.).
(Initially 25 – 30mins)
Key Question:
What happens when you remove stones from the soil?
Activity: Working in small groups, you will conduct a series of experiments to find out what
happens to the soil when stones are removed. First, you will need a tray (with lots of tiny holes
in the base) that is strong enough to hold approximately 2-3 kilos of soil. You will need an
assortment of different sized stones and 2-3 kilos of soil! A litre container filled with water. A
stopwatch. The tray should be placed over something to catch any water or conducted outside.
Sift the soil to make sure there are no stones in the soil. Place the soil in the tray. The tray will
need to be supported about 30cm from the ground. One person will need to be ready to pour
water, from the litre container, while another person holds the stopwatch. When everyone is
ready, start pouring the water and start the stopwatch at the same time. How long did it take for
most of the water to drain through the soil? Make a note of the time. Fill the litre container with
water again. Mix half of the stones with the soil. Repeat the litre container and stopwatch test,
making a note of the time. Finally, mix all of the stones with the soil and repeat the test.
Were the noted times different? Why?
What would be the difference if you used dry soil for each test?
(Key Stage 1: Science: Sc1 1. 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h, 2i, 2j. ICT: 1a,1b, 1c. 2a, 2b, 2c.
Key Stage 2: Science: Sc1 1a, 1b. 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h. ICT: 1a, 1b, 1c. 2a, 2b.)
Before planting, the potatoes (tubers) are left to sprout (chitting). This process helps
the potatoes to grow faster and produce heavier crops. Without chitting, the tubers
may grow too slowly.
Q
What do you think would happen if the tubers were planted before allowing them to
‘chit’?
A
The tubers would be slow growing and produce a poor crop
(Key Stage 1: Science Sc2: 3a b c
Key Stage 2: Science Sc2: 3a b c)
Q
Do tubers ‘chit’ better in warm, dark conditions or cold, light places?
A
The ‘chitting’ process works best in cool, well ventilated conditions and not placed
in direct sunlight. Ideally, sprouts should be about 5cm long and dark coloured.
Long, thin sprouts are caused by heat or too little light or both, while tiny sprouts
suggest conditions are too cold. Chitting takes about six weeks.
(Key Stage 1: Science Sc2 3a b c
Key Stage 2: Science Sc2: 3a b c)
Small Group Work
Key question:
(initially 25 - 30 mins)
What are the best conditions for potato tubers to chit?
Activity
The aim of this activity is to experiment with different ‘chitting’ conditions and analyse the
results. Each group should have an equal amount of tubers, various containers (plastic bag,
egg box, cardboard box, plastic tub, plant pot, tray) and an assortment of packaging.
Each group should discuss the various conditions they can provide to chit the tubers. For
example, they might like to consider keeping the tubers in the dark/cold, dark/warm, light/cold,
or light/warm. The group should also experiment with the various containers for chitting the
potatoes.
The groups should check on their tubers on a regular basis for sprout development, average
length of sprout, number of sprouts on each tuber and the condition of each tuber, some
sprouts may appear more wobbly than others. The results should be recorded over a six week
period on the grid below.
(Key Stage 1: Science Sc1 1 2a b c d e f g
Key Stage 2: Science Sc1 1a b 2a b c d e f g h)
Week
1
How many sprouts?
Length of sprout
Condition
2
How many sprouts?
Length of sprout
Condition
3
How many sprouts?
Length of sprout
Condition
4
How many sprouts?
Length of sprout
Condition
5
How many sprouts?
Length of sprout
Condition
6
How many sprouts?
Length of sprout
Condition
Container
1
Container
2
Container
3
Container
4
Potatoes are usually planted in April into warm, loose soil. The planter follows the beds
created by the stonepicker planting the potatoes into rows, which are ridged. The ridges
help prevent the tubers from becoming exposed to light and assist with the harvesting
operation later.
Q
What happens to potatoes that are exposed to sunlight?
A
Potatoes turn green due to prolonged exposure to light. The green colour
is due to the presence of chlorophyll, which is a natural plant pigment and
is tasteless and harmless. The chlorophyll is used by plants to turn the
light energy into food by photosynthesis.
(Key Stage 1: Science Sc2 3a b c
Key Stage 2: Science Sc2: 3a b c)
Q
Can you eat green potatoes?
A
The greenish colour, or chlorophyll, is an indicator that an alkaloid, called
solanine, may be present under the skin of the potato. Solanine develops
in potatoes when they are exposed to light (which also encourages
chlorophyll formation). Although it is toxic, it would take a very large
number of green potatoes to make you ill.
(Key Stage 1: Science Sc4 1d 2a
Key Stage 2: Science Sc4: 1d 2a)
Small Group Work
Key Question:
(15 - 25 mins)
Does the colour or shape of a potato make it more or less desirable?
Activity You will need portions of previously prepared mashed potato, defrosted oven
chips, and 15-20 peeled, small potatoes. You will also need a selection of food colourings
and small containers.
Divide the potato selection equally amongst the groups. Ask each group to discuss which
colours to use for the different potato dishes. They might like to consider dividing each
potato dish into two or three separate portions and using a different colour for each portion.
For example, the mashed potato might have one portion coloured blue, another green and a
third red. Once each group has completed colouring their potato dishes, ask them to label
each coloured potato dish.
Each group will require pen and paper. The groups are then to visit each others coloured
potato dishes and comment on the coloured potato dishes, answering the following
questions:
Would you eat this potato dish?
Why?
What were your first thoughts on seeing the potatoes coloured in this way?
Why does colour make a difference to the way we think about food?
(Key Stage 1: Science Sc1: 1 2a b c d e f h j
Key Stage 2: Science Sc1 1 2a b c d e f h i j)
Underground tubers grow to about 7cm long and swelling to 4cm wide on average.
They have a white, pinkish red skin depending on variety, and have a white flesh.
The soil is ‘earthed’ up as they grow leaving a small amount of foliage showing. This
helps stop the potatoes going green, weeds growing, and protects against frost.
Q
Why is it important to ‘earth up’ the growing potatoes?
A
To help prevent blight (disease), weeds growing and the potatoes going
green. Both weeds and blight would reduce the amount of potatoes grown
(yield), while potatoes that have green colouring are usually discarded.
(Key Stage 1: Science Sc2: 3a b c
Key Stage 2: Science Sc2 3a b c)
Q
Are there any other ways of helping to prevent weeds, blight and potatoes
turning green?
A
Straw is sometimes spread over the emerging potatoes to prevent weeds
growing and help stop blight. Other times plastic or fabric sheets are
spread over the flowering plants, which also helps protect against frost.
(Key Stage 1: Science Sc1 1 2a
Key Stage 2: Science Sc1 1 2 a)
Group Work
(initially 30 – 45 mins)
Key Question:
What material or substance is the most suitable for preventing weeds?
Activity You will need a selection of different materials. For example: cardboard, carpet,
clear/black plastic sheet, newspaper, chipboard and straw. Each piece of material should be
approximately 30x30 cm. For this activity you will need to have access to a section of
neglected or unused garden or lawn. Place each of the materials on a section of the garden or
lawn, using stones or wooden pegs to stop the material moving. The pupils should make a note
of the date, weather conditions and season that the activity started and suggest which material
they think will be the most successful in preventing weeds growing. The pupils should check
the materials each week, making a note of the condition of the material, weather conditions
and what is happening under the material. After an agreed time period, possibly 3-4 weeks, the
pupils should make a final examination of the materials and judge which has been the most
successful in preventing weeds. A graph could be made showing how successful each material
was in preventing weeds and what happened to the materials during the experiment. For
instance, did the weather have any impact on the condition of the materials?
(Key Stage 1: Science Sc1: 1 2a b c d e f g h
Key Stage 2: Science Sc1 1 2a b c d e)
The potatoes have a small white or pink flower and develop a small green tomatolike fruit that is poisonous to eat.
Q
Why do potatoes have brightly coloured flowers?
A
Coloured flowers attract insects such as bees which then help pollinate the plant.
(Key Stage 1: Science Sc2 3a b c
Key Stage 2: Science Sc2 3a b c)
Q
How do insects and bees pollinate the plant?
A
The insects and bees, attracted to the plant by the flowers, crawl inside the flower for
the sweet nectar usually deep inside the flower. As the bee searches inside for the
nectar, it gets covered with yellow pollen. It’s likely that the bee will fly to many flowers
of the same type of plant during the day, pollinating them one by one.
(Key Stage 1: Science Sc2 c
Key Stage 2 Science Sc2 c)
10 – 15 mins
Individual work
Key Question
Can you name the different parts of a flower?
Activity
Name the different parts of a potato flower by selecting titles from the list below:
Petal
Stigma
Style
Anther
Sepal
Filament
(Key Stage 1: 3a b c
Key Stage 2: Science Sc2 3a b c)
Pedicel
Ovary
Receptacle
The parts of a potato flower.
A harvesting machine does the job of lifting and separating the potato from the soil.
Some potatoes will be sold immediately and others will be stored so they are available
all year round.
Q
How were potatoes harvested before the invention of tractors or machinery?
A
At first, labourers harvested potatoes by hand carrying sacks around their waist.
Later, horses were used to pull specially designed potato digging equipment.
(Key Stage 1: History 2a 3 4a Key Stage 2: History 3 5a)
Q
Can machines carry out all the jobs involved in the potato harvest?
A
Commercial harvesting is usually done by potato harvesters, which scoop up the
plant and the surrounding soil. The harvester then separates the potatoes from the
plant and then workers sort out plant material, stones, and rotten potatoes before
the potatoes are delivered on a conveyor belt to a truck.
(Key Stage 1: History 2a b Key Stage 2: History 2c d)
Small Group Work
25 – 30 mins
Key Question
Does rainfall make any difference to the amount of potatoes harvested?
Activity
Working in small groups the pupils are to produce a line graph using the information supplied.
The design and type of the graph is to be decided by the pupils with the appropriate key and
colours used to identify the data.
Once the graphs have been produced, the pupils should try and answer the following
questions:
Which year produced the most potatoes?
Which year produced the least amount of potatoes?
Does rainfall make any difference to the amount of potatoes produced?
Why do you think this happens?
(Key Stage 1: Geography 4a b
Key Stage 2: History 4a b)
Data:
Potato Crop (1000kg per 10,000sq metres)
2000: 44
2001: 48
2002: 36
2003: 45
2004: 38
2005: 46
2001: 146
2002: 37
2003: 101
2004: 68
2005: 106
Rainfall (mm)
2000: 98
The first earlies are usually harvested by the middle of July. In August the second
earlies are being harvested. Potato picking is now mechanised with machines lifting
and off-loading the crop in one operation.
Q
Can potatoes grow in any type of soil?
A
The ideal soil for growing potatoes is sandy, well drained and having lots of
nutrients. Poorly drained soil will cause the seed potatoes to rot before they
sprout.
(Key Stage 1: Geography 1a Key Stage 2: Geography 1a)
Q
Do potatoes need to be planted in a field to grow?
A
Although commercially grown potatoes are planted in fields, there are lots of other
ways to grow potatoes. You can use buckets, tubs, boxes, bags and bin liners.
(Key Stage 1: Science Sc2 3a
Key Stage 2: Science Sc2 3a)
Small Group Work
Key question
initially 35 – 45 mins
What is the best way to grow potatoes on a small scale?
Activity
You will need a large bag of seed potatoes, egg boxes, potting compost and several types of
container for growing the potatoes. Each group will decide which type of container to use for
growing their potatoes.
The potatoes should be placed in an egg box with the eyes (a bud on the potato tuber) up, the
baby shoots will grow from the eyes. Then, place them in a cool but light place until they begin
to shoot and show little green fat leaves.
Fill the chosen container one-third full of soil and make a few holes with a pencil in the bottom,
so that water can drain away and the soil does not become waterlogged.
Plant 2 or 3 potatoes in the container, with the shoots pointing upwards. Cover with potting
compost so that the container is half-full. Give the container a good watering and place it
outside in a sheltered place.
When the shoots are 15-30cm tall, you can add more compost until the container is completely
full. This is called earthing-up and it encourages the potatoes to make more stems, and more
potatoes, as well as stopping light reaching the potatoes that have already formed. The
potatoes can be harvested about 10-12 weeks after planting.
Which type of container produced the most potatoes?
(Key Stage 1: Sc2 3a b c Key Stage 2: Science Sc2 3a b c)
Potatoes are grown in rotation and do not come back to the same field for at
least 5 years. If potatoes are grown more regularly, damaging pests might build
up in the soil and destroy a crop.
Q
Why is it important to grow crops in rotation?
A
Crops are grown in rotation to avoid particular pests and diseases developing
the soil and spoiling the crops.
in
(Key Stage 1: Science Sc1 2a Key Stage 2: Science Sc1 2a)
Q
Why is soil so important?
A
Plants need soil to grow properly. Soil is where minerals, water and air are worked
on by micro-organisms to provide the right conditions for plants to grow.
(Key Stage 1: 2a
Key Stage 2: Science Sc1 2a)
Small group Work
Key Question
20 – 25 mins
Are there different types of soil?
Activity You will need to collect soil from a variety of locations, ensuring that you have as
many different types of soil as possible. Place a selection of soil types into small containers
and distribute amongst the groups. Each group should add sufficient amount of water to be
able to knead the soil into shapes.
The groups should try and mould each soil sample into one of the shapes listed below to
identify the soil type.
Shape
Cone
Ball
Worm
Cracked worm
Smooth worm
Type of soil
Sand
Loamy sand
Loam
Clay loam
Clay
What soils did the groups identify?
Were the soil types different in any other way? For example, colour, smell, size of
granules?
Did some of the soil types dry out quicker than others?
(Key Stage 1: Science Sc1: 2a b e f Key Stage 2: Science Sc1: 2a b c d)