Hot pot

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I.S. Project

• Hot pot

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Content

• Enjoy hot pot safely-----------------------P.3,
  P.4
• Preparation of food------------------------P.5-P.8
  
• Cookbook and cooking method of hot pot-P.9
• Cooking Method----------------------------P.10,
  P.12
• Hot hot pot-------------------------------P.11
• Balance diet--------------------------------P.13-1
  5
• Heat Transfer-----------------------------P.16
• Conduction----------------------------------P.17-2
  0
• Convection----------------------------------P.21-2
  4
• Radiation------------------------------------P.25-
  28
• Oven and Fuel-------------------------------P.29-3
  5
• Use hot pot gas appliance safely-----------P.36-39
  
• Group member------------------------------P.40

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Enjoy hot pot safely

• While cold spells always attract people to
  the warm fun of hot pot, one should take all
  necessary precautions against possible health
  hazards.
• Among the goodies available for hot pot,
  seafood is probably the most favourite. However,
  since seafood is a high-risk food item, people
  are advised to clean and cook it thoroughly
  before eating . Only with proper handling are we
  able to destroy such pathogens as Hepatitis A
  virus, Vibrio parahaemolyticus (a food poisoning
  organism) and parasites possibly contained in
  seafood.

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• In addition , winter is the high season
  of Hepatitis A occurrences. Raw seafood,
  particularly shellfish, is a known carrier of the
  Hepatitis A virus. Coupled with the fact that
  this virus is more active during winter, the
  danger of contracting the disease is higher if we
  consume shellfish that is not properly done.
• Therefore , people are strongly advised
  to take the precautions while enjoying hot pot.

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The preparation of the food (washing and
cooking)

• If you want to enjoy hot pot , he most
  important thing is to cook the food thoroughly !!
• Here are the necessary precautions we
  have to bear in mind in order to against possible
  health hazards

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• Add food to boiling water only, especially
  after topping up with unboiled water.
• Cook food thoroughly before consumption.
  Shellfish should be cooked in boiling water for
  not less than five minutes while meat should not
  be pink in colour when eaten.
• Avoid dipping cooked food into raw eggs, as
  pathogens inside the eggs may contaminate the
  cooked food.

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• Avoid cross contamination by
  using two sets of chopsticks and eating
  utensils to handle raw and cooked food
  separately.
• Avoid placing too many dishes of food on the
  table at one time to prevent cross contamination.

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Here are the preparation of the food (The thing
we have to remember is always keep our hands
clean while preparing the Hot Pot)

• Wash food such as shellfish, meat and
  vegetables thoroughly. Remove internal organs
  from the shellfish.
• Store hot pot materials in a refrigerator at
  four degree Celsius or below and take it out for
  cooking only when necessary.
• Do not leave cooked food at room temperature
  for more than 2 hours.

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The cookbook and the cooking method of Hot Pot

• -Seafood Hot Pot
• Ingredient
• The fish flesh, the shrimp, the trepang, the
  flowering branch, the vegetable, the
  chrysanthemum coronarium lettuce, Jin Chenku, the
  milk-fish pill bean curd, the potato, the crab
  stick and the Korean vegetable.

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Cooking Method

• -Wash all of the materials thoroughly
• -Cut the food materials into pieces
• -Put a large amount of boiled water as well as
  all of the food materials into the pot
• -Add little chicken powder as seasoning to make
  the Hot Pot more delicious

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• HOT Hot Pot
• Ingredient
• Winter powder, pig tripe, pork, flowering
  branch pill, tribute pill, frozen bean curd, Mi
  Hsuehkao, duck blood, chrysanthemum coronarium
  lettuce, small colza lily flower, Korean
  vegetable and onion

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Cooking Method

• a) wash all of the food materials thoroughly
• b) Bare the small colza and the Korean vegetable
  into one piece by piece, slightly Sichuan burns.
  Cut the lily flowers root, and cut the onion
  into sections .
• c) Put a large amount of boiled water as well as
  all of the food materials into the pot
• d) Add a lot of Hemp hot sauce as seasoning to
  make the Hot Pot more delicious

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The Balanced Diet

• A diet containging the right amounts of all
  the food sunstances is known as a balanced diet
• Man needs a wide range of nutrients to
  perform various functions in the body and to lead
  a healthy life. The nutrients include proteins,
  fat, carbohydrates, vitamins and minerals. These
  nutrients are chemical substances which are
  present in the food we eat daily. The foods
  containing these nutrients which we consume daily
  are classified as cereals, legumes (pulses), nuts
  and oilseeds, vegetables, fruits, milk and milk
  products and flesh foods (fish, meat and poultry)
  .

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• By the way , we also need these nutrients
  when having our delicious Hot Pot !

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• On the other hand , we have to pay
  attention to the following point when having our
  Hot Pot
• a) A person who have cardiovascular disease
  should avoid eating food like fish ball as they
  contain a large amount of fat or oil
• b) A person who have kidney disease should avoid
  drinking soup containing potassium ions and
  sodium ions
• c) Avoid using seasoning containing a large
  amount of salt and oil since they are all
  unhealthy food

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Transfer of Heat

• When you are having your delicious , do
  you have tried to think about how is the energy
  transfer from the oven to the pot , and then to
  the food?

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Conduction

• Let us first investigate how energy is
  transferred by conduction from the oven through
  the pot to the food .
• Conduction occurs when energy is passed
  directly from one item to another. If you stirred
  a pan of soup on the stove with a metal spoon,
  the spoon will heat up. The heat is being
  conducted from the hot area of the soup to the
  colder area of spoon.

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• Metals are excellent conductors of heat
  energy. Wood or plastics are not. These "bad"
  conductors are called insulators. That's why a
  pot is usually made of metal while the handle is
  made of a strong plastic.

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• According to the kinetic theory ,
  particles in a solid are closely packed . They
  vibrate to and fro but cannot change positions .
  Particles at the hot part of the food vibrate
  more than those at the cold end . The fast
  vibrating particles bumping onto the slower
  neighbouring particles and make them vibrate more
  rapidly . In this way , energy is transferred ,
  from one particles to the next , and from the hot
  to the cold end of the food .

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There is a method to calculate the conduction of
heat transfer
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Convection

• Convection is the transfer of heat by
  the motion of or within a fluid. It may arise
  from temperature differences either within the
  fluid or between the fluid and its boundary, or
  from the application of an external motive force.

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• When water at the bottom of the beaker is
  heated , it expands , rises , and is replaced by
  cold water coming down from above . The flow of
  water is called convection current .

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• Have ever you had a hot pot meal in the
  winter? You may notice that the food keeps moving
  up and down in the water even when the
  temperature is well below that of boiling. This
  indicates that bulk movement of water exists when
  it is being heated. In fact, this movement of
  water serves as an effective way of heat
  transfer, especially when the rate of heating is
  high.

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• Convection can also be calculated by the
  following method
• The local convective heat flux of a fluid
  passing over a surface is expressed as
• q" h (Ts - T8)
• q" local heat flux (dq/dA)
• h local convection coefficient
• Ts surface temperature
• T8 quiescent or ambient temperature
• The total heat transfer over a surface is
  then calculated as the integral of q",
• q ?Asq" dAs
• As area of the surface
• q total heat transfer rate (units of
  energy/time)
• This then leads to a definition of average
  convection coefficient, h-bar, defined from
• q h-bar As (Ts - T8)

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Radiation

• The sun shines and warms our body. The
  energy is carried through the vast space between
  the sun and the earth by radiation. Unlike
  conduction and convection, radiation does not
  need a medium to transfer energy the energy is
  carried by electromagnetic (EM) waves. Light is a
  kind of EM waves that is visible to naked eyes.

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• Radiation is the process of heat
  transfer by electromagnetic waves.
• A hot object gives out energy by
  radiation in the form of EM waves. Objects on
  fire give out visible light because of their high
  temperatures. Objects at normal temperature range
  give out mainly infrared radiation that is
  detected by our skin as warmth. Place your hand
  near the side, but without touching, of the oven
  and you will feel warmth. If the emitted
  radiation is absorbed by a colder object, the
  colder object will gain internal energy and rise
  in temperature.

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• The higher the temperature of the object,
  the higher the amount and more energetic the
  radiation it emits. A cool object still radiates
  energy but less than a hot object. Consider your
  hands as being warmed by the infrared radiation
  from a lamp for example. Though your hands also
  radiate energy, the lamp radiates energy to your
  hands at a much higher rate and thus your skin
  has a net gain in energy and an increase in
  temperature.

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• The appearance of a surface determines
  its rates of emission and absorption of
  radiation. In general, shiny coloured (e.g. white
  or silvery) and metallic surfaces , such as the
  pot , emit or absorb radiation energy slowly
  since they reflect the radiation. Dark coloured
  (e.g. black) surfaces emit or absorb radiation
  energy more effectively. It is interesting to
  note that a good emitter of radiation is also a
  good absorber of radiation and vice versa.

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Oven and fuel

• Let us first introduce some types and
  the uses of Hot-pot Gas Appliances.
• -Electrical Hot-pot Sets
• Specification Rating 100V / 240V 50Hz-60Hz
  ,1000W - 1200W
• FeaturesPF heating base with aluminum
  heating plate,Rotary temperature controller and
  pilot lampEasy to use, clean and store

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Gas stove

• The gas stove mainly uses Butane or
  Propane as fuel . Propanecan be more easily to
  vaporize , therefore the fire output is higher .
  It is suitable to be used in Snowy mountain .
  However ,the Gas storage holder of Propane is a
  litter bit heavier than that of Butane .
• On the other hand , Butane can be used
  more widely , It is more expensive than
  Propanecan , but it is easier to adjust the fire
  power .

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Liquid vaporization stove

• The Liquid vaporization stove mainly uses
  white gas and Kerosene as fuel . It utilizes the
  Preheating pressurizes the vaporization
  principle to increase the fire power . The
  Liquid vaporization stove is more expensive as
  its design is extremely complicated . On the
  operating aspect , it is also complicated since
  it is difficult to adjust the firepower . The use
  of the Liquid vaporization stove is
  environmentally friendly .

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Spirit-burning stove

• The Spirit-burning stove is the most light
  , portable as well as cheap among all of the
  stoves . It mainly uses Ethyl alcohol (methyl
  alcohol) as fuel . It is used by direct burning
  without Pressurizing . Its structure is very
  simple . However , the fire power and output is
  not high enough , it can only be used by just
  cooking little food

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Solid fuel stove (white wax stove)

• The Solid fuel stove (white wax stove)
  mainly uses Paraffin as fuel . It has simple
  structure and easy to use .However , the fire
  output and power is low .

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Convection Oven

• The modern Convection Oven can roast,
  broil, grill, bake or steam your favorite foods!
  When you don't have a lot of time to make dinner
  and your family is getting impatient, the
  Convection Oven can really come in handy.

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• You can cut your cooking time as well as
  save your money by using the Convection Oven.
  Since it cooks food in less time, you'll be
  cutting your cooking time which will then save
  you money on your electricity bill.
• Hot air circulates around your food in
  the Convection Oven, cooking it fast and evenly.
  Your meats will become seared evenly on the
  outside by the hot air, sealing in the juices for
  a tender steak or even a whole chicken.

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Use Hot-pot Gas appliances safely

• We should always follow the instructions
  that come with your hot-pot gas appliances .
• Many consumers turn to hot-pot food in
  cool weather. Some families use cassette cookers
  for hot-pots.

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To ensure gas safety while cooking, you should
follow the instruction manuals and note the
following precautions

• -Place the cartridge with the cartridge guide in
  up-right position
• -Do not use two cassette cookers in parallel

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• -Never fit/remove cartridge near naked flame or
  heat source
• -Use the cassette cooker in a well ventilated
  area and away from flammable materials
• -Use approved cassette cookers only (bearing
  "GU" Mark).

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• -Store cartridges in dry, cool and
  well-ventilated places.
• -Do not use hot-pots which extend over the edge
  of the cartridge covers
• -Do not use accessories not approved by
  suppliers.

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Group members

• Ching Chun Ming F.4E (7)
• Li Tsz Ho F.4E (23)
• Sin Wai Ping F.4E (28)

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The end