Transcript Food Packaging

Food packaging
Over the last 50 years the way we buy food has changed. In the past, some
food items were usually sold ‘loose’ and taken home in a paper bag.
Due to advances in technology, most food items are now sold pre-packed.
Food products often have a long journey from the initial manufacturer until
finally being eaten by consumers. They must be stored in warehouses before
being transported and distributed to retailers.
They are then likely to be stacked in more warehouses before being sold.
At all these stages the product may be damaged by careless handling or
changes in storage conditions such as light, humidity and temperature.
The aim of packaging is to contain the product and keep it intact.
This means that liquid products do not leak and that dry materials, such as
flour, do not spill out.
It is sometimes necessary to design packaging that is shaped especially to
contain a particular food, e.g. egg boxes, so that the product is held securely
and well protected from damage.
© Food – a fact of life 2012
Major part of food production
The packaging of fresh and any other food products is a major factor in food
production for numerous reasons:
• Food hygiene – people handling fresh foods before purchase, causing
damage and transfer of bacteria. The need to prevent wastage and food
spoilage, for the producer and consumer alike.
• Packaging design is vital for the five P’s = Preservation, Presentation,
Prevention of tampering, Protection, Promotion. (Any discussion relating to these points
will gain marks in the examination)
• The food industry relies heavily upon the work of packaging designers,
providing employment and income when good designs are patented and
sold to other companies and parts of the world.
• The desire for fresh soft fruits – numerous recipes that contain them, bright
colours and sweet, sharp taste, five a day, phyto-chemicals, anti-oxidants,
nutritional value.
• Issues relating to the environment, such as raw materials to produce
packaging, air miles if foods are to be transported across the world, recycling,
biodegradable etc. (see further info later)
• Consumer expectations – the fact that consumers are now used to effective
packaging for delicate foods. They want to be able to see the food before
they buy it; they want it to be stored correctly, easy to transport home and
store in a fridge or freezer.
© Food – a fact of life 2012
Foundation
The purpose of packaging
The aims of packaging include:
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.
• prevent contamination from micro-organisms and pollution
• dehydration or dampness
• protect the product’s nutritional and sensory characteristics
Containing – Packaging contains the contents:
• so that they can be transported, stored and displayed easily.
• can make awkwardly shaped products easy to handle.
© Food – a fact of life 2012
Preserving –
• Packaging can be part of the preservation process such as tin cans
and modified atmosphere packaging (MAP)
• help to increase a product’s shelf life
Identification/information –
• Packaging describes and identifies the contents and provide
information
• 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.
© Food – a fact of life 2012
Labelling
Packaging is also designed to be visually stimulating and provide
information about the product to help the customer.
The information supplied must cover:
• the name of the food
• the weight/volume (metric) (unless under 5g)
• the list of ingredients in descending order of weight
• how the food should be stored, where appropriate
• the date when the food should be eaten
• genetically modified ingredients and allergens
• the name and address of manufacturer or distributor
• nutrition information on the back of pack (from 2016 onwards).
The manufacturer may choose to provide extra information, e.g.
preparation and cooking instructions, the place the food comes
from and a bar code to identify the food.
The overall design of packaging, from its shape to the style of writing
used, indicate the type of product it contains and for whom it is
intended. It may also use ‘graphical’ tricks to give a sense of
quality, e.g. that it has been hand made.
© Food – a fact of life 2012
Consumer information
Food assurance schemes have been developed to compliment food
legislation. They cover the food chain from farm to fork.
An example is the Red Tractor food assurance scheme
It covers:
• cereals, oilseeds, pulses and sugar;
• fruit, vegetables and salad;
• milk;
• chicken;
• beef, lamb and pig meat.
Multi-ingredient products must contain at least 65% Red Tractor certified
ingredients to be labelled as Red Tractor products.
The Red Tractor logo can only be used to label ingredients from farmers,
growers and food processors that have been inspected and certified to strict
standards. Detailed technical standards that cover:
- food safety: makes sure your food is safe to eat
- animal welfare: makes sure animals have everything they need for a good
quality of life
- environment: makes sure farmers protect the countryside by preventing
pollution of watercourses, soil, air and wildlife habitat
- traceability: every part of the food supply chain is inspected to ensure food
carrying the logo is accounted for and can be traced back to UK farms.
© Food – a fact of life 2012
Packaging design
When designing packaging it is important to consider the following:
• Is it easy to handle and open?
• Is it a convenient shape, so it is easy to stack?
• Which colours will be used on the packaging?
• What size of print should be used?(Can consumers read it easily?)
• Will it be economical to produce?
• What about environmental considerations? (Will it be recyclable
or does it make minimum use of natural resources?)
Increased rates of production during the last few decades have
made it necessary to use different methods and materials to pack
and protect food products.
However, other factors also determine the choice of materials used,
especially in relation to food hygiene and safety. For example, the
material must be suitable for the food, as some chemicals present
in the food or packaging may react together.
© Food – a fact of life 2012
Example: Food cans
Cans were traditionally made from tin plate sheet, but now more
commonly aluminium is used (for drinks).
The inside of the can is often sheet coated with lacquers to prevent
the cans rusting and reacting with the contents, especially acidic
foods.
Example: Paper, board and foil
Paper, board and foil are commonly used to package foods. Board
used for food packaging is often coated with a wax of polythene to
prevent interaction with contents.
Most paper or board should be discarded before heating, but some
products frozen on specially treated board may be cooked in
microwave ovens.
Foil trays are suitable for both freezing and heating in conventional
© ovens.
Food – a fact of life 2012
Examples: Plastics
Food packaging uses a wide range of both rigid and flexible plastic
materials including:
• polythene – low density is used as a film wrapping, resistant to
water. High density is used for ‘boil-in-the-bag’ products;
• polyamide (nylon) – provides a very good barrier to oxygen, so
used for vacuum packaging, especially for foods containing fat
(which can be susceptible to oxidation).
• polyethlene terephthalate (PET) rigid plastic bottles, light-weight,
little risk of breakage and keep the fizz in carbonated drinks;
• polystyrene – expanded polythene used for trays and insulated
containers to keep food products cold, e.g. ice cream and sorbets
or hot, e.g. coffee, soup and burgers.
Example: Cellulose films
Cellulose films are used for different types of food packaging, because they
have a range of characteristics such as different degrees of moisture
proofing.
Some cellulose films are heat sealable.
They can be used, for example, as window patches in cartons.
© Food – a fact of life 2012
Example: Glass
Glass has been used for food packaging for a long time but tougher,
light–weight containers, sometimes protected by a sleeve of
expanded polystyrene have been developed more recently.
However, glass is still very popular and is used exclusively for many
products, e.g. jam.
Example: Modified atmosphere packaging
Modified atmosphere packaging (MAP) is a technique used to
lengthen the shelf-life of food products of minimally processed or fresh
foods.
The air surrounding the food in the package is changed to reduce the
activity of microorganisms.
Meat, fish, fruits and vegetables often use the method during
packaging.
Equilibrium modified atmosphere packaging (EMAP) is most commonly
used for cut fresh-cut produce.
© Food – a fact of life 2012
Modified Atmosphere Packaging (MAP)
and ambient foods
Chilling foods can have a preservative effect by retarding microbial
activity. However, the shelf-life of a chilled product can be increased
by modifying the gases surrounding the food.
Modified Atmosphere Packaging is also known as 'Controlled
Atmosphere Packaging CAP'.
It is the enclosure of a food e.g. bacon, in a package in which the
atmosphere has been changed by altering the proportions of carbon
dioxide, oxygen, nitrogen, water vapour and trace gases. Food is
consequently preserved in sealed gas flushed packaging.
The process limits microbial as well as biochemical activity.
A wide variety of products are gas flushed, typical products:
Fresh and processed meat/poultry, fish and seafood, cheese, milk
powder, ready meals, fresh pasta, fruit and vegetables, salad leaves
© Food – a fact of life 2012
• Air is removed and replaced by a controlled mixture of gases. The
ratio of these gasses depends upon the food being packaged.
• In the packs the oxygen level can be lowered or the carbon
dioxide level or nitrogen levels increased.
• - CO2 slows the growth of bacteria.
- Oxygen helps retain the colour of the food, e.g. meat stays red
- Nitrogen is used to reduce the rate of oxidation (e.g. fruit and
vegetables going brown)
• The food is prepared and placed in the container.
• The container is then flushed with the selected gas for the food
type and is then hermetically sealed.
• MAP is often carried out in conjunction with chilling in the case of
chilled meals or prepared salads.
• Once the packaging is opened the food has a normal shelf life and
must be stored accordingly.
• The packaging used must be non reactive and sufficiently strong to
resist damage through piercing or splitting.
• The most commonly used materials are plastics, which may be
ovenable, with a film cover.
© Food – a fact of life 2012
Thermoplastic polymers
Nearly all packaging for this process is based on thermoplastic
polymers. The reasons for this are that they:
• have greater flexibility, i.e. can be formed into different shapes
• are light in weight
• provide a gas barrier
• can be sealed easily
• can be printed on
• are resistant to physical pressures of manufacturing, distributing
and retailing
• have good aesthetic properties
• can be multi-layered with other materials to enhance overall
properties.
© Food – a fact of life 2012
Proportion of gases in packaging
© Food – a fact of life 2012
Proportion of gases
© Food – a fact of life 2012
Vacuum packaging
• Vacuum packing is a method of packaging that removes all
air/oxygen from the package prior to sealing, so that the organisms
requiring it to reproduce are inhibited (thus extending shelf life).
• This method involves (manually or automatically) placing items in a
plastic film package, removing air from inside, and sealing the
package.
• Shrink film is sometimes used to have a tight fit to the contents.
• The flexible package forms reduce the volume of the contents and
package
• The materials used for vacuum packing should be resistant to
piercing and splitting, but equally, be resilient to the process and
able to comfortably form around the food.
• Suitable materials for vacuum packing dry goods are foil packages,
e.g. ground coffee and nuts or robust plastics, suitable for storage
in a refrigerator, e.g. for cooked meats or smoked fish.
• The material should be non-reactive with the food.
© Food – a fact of life 2012
• It is commonly used to store dry foods over a long period of time,
such as cereals, nuts, cured meats, cheese, smoked fish, coffee,
and potato chips.
• On a more short term basis, vacuum packing can also be used to
store fresh foods, such as vegetables, meats and liquids, because it
inhibits bacterial growth.
• It would normally not be suitable for delicate food that need to be
kept intact and might be crushed by the vacuum packing process
e.g. berries, cakes etc. delicate food items
If vacuum packaging food in the home, the food should be eaten
within ten days. The packet should be sealed and left in the fridge
until it is eaten to keep it safe. Once the packaging is opened, it
should still be kept in the fridge like other chilled foods and eaten
within two days.
© Food – a fact of life 2012
Ambient food products
Ambient foods are those which are stored and sold at room
temperature.
Canned and aseptically packaged foods are examples of ambient
products, e.g. ready meals, fruit juices, UHT milk.
They are intended to have a long shelf-life, and undergo rigorous heat
treatment to destroy potentially harmful microorganisms.
Pasteurisation and sterilisation are the two main heat processes used.
Some ambient foods are not heat treated, e.g. cereals.
Only harmless micro-organisms can be allowed to survive processing
treatment. Canned fruit juice, which may contain spore-forming
bacteria, will be safe as long as the pH is low enough to ensure the
bacterial growth could not occur.
Low-acidic foods undergo a rigorous heat treatment known as the
‘Botulinum cook’ – to reduce the numbers of clostridium botulinum
spores to a safe level. This is because these spores are very resistant to
heat.
Ambient foods, such as cereals, rice and pulses must be stored
carefully.
The moisture content for each needs to be kept low to prevent mould
and yeast spoilage.
© Food – a fact of life 2012