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					         How is Cows’ Milk Collected?
                                                     Milk production
Effects that milk collection can have on the         •   Cows spend about 8 hours a day
    environment include:                                 eating, 8 hours a day sleeping and 8
•   wastes from spilled milk that the machines           hours a day rummaging or chewing
    miss from the cow can spoil the environment,         their own cud.
    and become useless since the milk isn’t usable   •   Cows are milked twice daily, 6 a.m.
    by anyone                                            in the morning and again at 5 p.m.
•   greenhouse gases generated from the burning          in the evening.
    of the brown coal used to make the electricity   •   Milking time is 5 minutes per cow;
    which operates the machines for milking and          usually it depends on the type of
    refrigerating the milk will contribute to the        machinery that the dairy farm has.
    ‘enhanced greenhouse effect ’                    •   Most dairies have enough machines
•   noise that the machines produce when milking         to milk 20 to 30 cows one at a
    the cows can disturb people around the area,         time.
    although most dairies are out in the country
    and away from houses
•   odour from the raw milk as well as the cows
    themselves can affect people close by.




Sustainable actions: minimise spillages,
workers wear ear muffs, turn off electricity
to milking machines when not used.
        How is Cows’ Milk Processed?
    Milk, once it comes from the dairy, has to first go through the process of pasteurisation. What
      happens here is that the milk is stored in a machine called a ‘pasteuriser’ and goes through the
     stage of getting heated up to 64 oC for 30 minutes, or 72oC for 15 seconds, and then is quickly
     cooled again. This is designed to destroy almost all of the bacteria in the milk, as well as disease
       agents. Pasteurisers use electric heat to warm the milk and require a tap water supply. Some
     pasteurisers also can provide warm drinking water for cows. The milk is then cooled and stored
                                                at 4˚C or less.


Effects that pasteurising can have on the environment:
•    Wastewater is a major environmental let down in the milk industry in terms of wastage of
     resources and polluting effects. Wastewater effects include algal blooms in waterways and soil
     degradation.
•    The use of electricity is another part of the process that affects the environment. The demand
     for milk is very high and Victoria produces two-thirds of Australia’s milk. With the more milk
     we have to produce, the more electricity is needed to heat and cool the milk during
     pasteurisation. Electricity generated from Victoria’s brown coal supplies is using up this non-
     renewable fossil-based resource – and is therefore unsustainable - as well as contributing to
     greenhouse gas emissions through the burning of the coal to produce CO 2.
•    Waste emissions from dairies also affect the environment. The main emissions
     from the manufacturing processes are odours and particles; these may cause
     respiratory problems as well as contribute to air pollution.
•    Noise pollution is present when pasteurisation occurs. Some of the sources of noise pollution
     include: heater fans; boilers; pumps; ventilation systems; air supply fans; cooling towers;
     refrigeration units.

    Sustainable actions: monitor wastewatewater and emissions effects and come up with a management
    plan for the company, consider alternative energy sources for running machinery and carbon offsets
Wastewater sources and environmental effects
     Depending on how the processing site is arranged and the types of waste minimisation strategies used at
the site, the volume of wastewater produced during milk processing may be as high as two-and-a-half litres of
wastewater per litre of milk processed.

The main sources of dairy processing plant wastewater are:
- raw material and product losses from leaking equipment and pipelines
- spills caused by equipment overflows and malfunctions
- foaming of the milk from being heated at such high temperatures
- poor handling procedures during processing, including use of materials for cleaning and
sanitising to ensure that the machinery is hygienic and clean
- deposits on pasteurisation surfaces and heating equipment.

Poorly treated wastewater can cause problems for the environment, including:
• excessive concentration of nutrients such as nitrogen and phosphorus in the surface of waterways and sub
surfaces. This causes excessive growth of plants and algal blooms which makes downstream water unsuitable for
agricultural use.
• land and soil degradation, which can damage pastures and crops. Long term damage to the soil productivity
can happen due to:
     - salinity
     - excessive nutrient loading
     - over application of wastewater to land causing contaminated ground water, poor irrigation, clogging of
soils by fat/solids from irrigated wastewater, soil structure decline because of the wastewater having such a high
sodium (salt) absorption capacity
     - low or high soil acidity (pH).

Sustainable actions: monitor and traet wastewater sources and contribute money and iseas to a
management plan for local sites of land degradation; audit efficiency of machinery and practices
                                 Homogenisation
  Once milk has been pasteurised, it then goes through a process called
homogenisation. Milk has to be homogenised because otherwise a layer of
                      cream forms on the top of the milk.
 Homogenisation is when the fat in the milk is separated from the rest of the liquid
and is broken up into smaller sizes. The broken up fat particles are then mixed evenly
   throughout the milk so that the fat no longer separates from the milk.
   The process involves pushing the raw milk through an ‘atomiser’, a tube which
                     contains tiny holes, to form tiny particles.




   Wastes from the homogenisation process include:
   • wastewater from liquid losses and leaks and also cleaning operations
   • greenhouse gas emissions from using electricity to power the process
   •noise pollution from the machinery
   • waste from the process including raw materials and product spillage.




  Sustainable actions: check machinery for leaks and spillage points,
  turn off electricity to machines when not in use, workers wear ear muffs.
    How is Cows’ Milk Packaged?
•         Milk is collected from the farm
    every 24-48 hours. The tankers that
    are used for collecting the milk are
    made of a stainless steel body that is
    heavily insulated to keep the milk cold.      Environmental impacts that can occur in the
    The milk is in the tankers until it gets         process of packaging milk in a factory are:
    to the processing factory.                    • use of electricity to power the machines
•        Once the milk is in the factory, it is      that package the milk into the bottles
    held in large steel containers until it is       and cartons contributes to greenhouse
    ready to get sent through metal tubes            effect (CO2 emissions) and depletes fossil
                                                     fuel resources (to make electricity)
    to be pasteurized.
                                                  • high water usage allocated to cleaning
•        Pasteurisation is a process that            the machines on a regular basis
    means to electrically heat the milk to
                                                  • the production of noise that is made by
    kill any bacteria that may be present in         the machines when the milk is being
    the milk. The milk is then cooled and            bottled.
    stored at 4˚C or less.
•        Once the milk has been pasteurised
    and homogenised it is sent through a
    processing line to be packaged into
    bottles and cartons.
                                                  Sustainable actions: turn off electricity when
                                                  machines not in use, consider electricity
                                                  alternatives e.g. solar power, conduct water
                                                  usage audit, ear muffs for workers
        How is Packaged Cows’ Milk
          Distributed to Shops?
Once the milk has
  been packaged
  into the bottles
  and cartons it is
  put into large      Environmental impacts that can occur in the
  refrigerated           process of transporting milk to shops include:
                      •   large quantity of petrol or diesel is used to put in the
  trucks to be            milk trucks and so uses up this resource
  sent to shops       •   smog that is emitted by the trucks when they are
  such as                 making deliveries to and from the farms, through
                          the burning of the petrol or diesel used
  supermarkets,       •   large amount of noise that the trucks make while
  cafes and               travelling
  restaurants.        •   high number of trucks that are needed to transport
                          the milk contribute to possible traffic problems.



                      Sustainable actions: consider alternative fuel sources
                      e.g. hybrid or hydrogen-based fuels, air and noise
                      pollution filters on trucks, consider non-peak hour truck
                      travel
    What Happens to the Waste at the
         End of Packaged Cows’ Milk
Environmental impacts that
                           Processing?
   can occur in the process
   of recycling milk
   containers are due to:
• the requirement for
   large volumes of water
   used to:                   Environmental impacts that can occur in the process
 - wash the bottles for          of transporting milk containers to the recycling
   recycling                     plant can be:
 - help turn the milk
   cartons into pulp to be    •   the use of non-renewable, fossil-based fuels (petrol and
   turned into new                diesel) being put in the transpostation trucks
   products.                  •   the large number of recycling trucks needed to transport
• the use of electricity to       the recycling goods to the recycling plants contribute to
   melt down the plastic          noise, pollution and traffic problems.
   milk bottles


Sustainable actions:                                 Sustainable actions: consider
consider water recycling,                            alternative fuel sources and
alternative energy sources,                          pollution filters for trucks
different packaging
How Does the Consumer Use Cows’
             Milk?
Milk is bought and used every single day by consumers. The consumers mainly use it for
         cooking and food, different types of beverages and for just drinking as it is.
Ways the consumer uses the product can also have an effect on the environment. Ways
                                    this can happen are:




 •   the use of electricity to power the refrigerator that keeps the milk cold and to
     power cooking appliances that heat up the milk. This contributes to greenhouse
     gas emissions because more coal is burned to power the electrical appliances.
 •   the production of waste from:
      - throwing out excess milk that is not used down the drain, which can then
     pollute water ways
      - disposal of packaging into waste dumps.
 •    the use of more fuel by the consumer uses more fuel to to drive their automobile
     to the supermarket to buy the product. This contributes to the air pollution
     through automobile emissions, and also uses up fossil-based non-renewable
     resources used to produce the fuel.

 Sustainable actions: consider alternative energy sources for powering refrigerators and
 cooking appliances such as solar energy, consider biodegradable and/or recyclable
 packaging, encourage consumer awareness of more sustainable travel options and consumer
 habits

				
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posted:8/18/2011
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Description: Supermarket Worksheet document sample